초록 ▼

A rockshaft is mounted over the front rank of the implement frame and is operated by cylinders located at opposite ends of the rockshaft connected to lift arms extending radially adjacent bearing mounts. Fore-and-aft extending links aligned with the lift arms and mounts operate lift wheel assemblies

A rockshaft is mounted over the front rank of the implement frame and is operated by cylinders located at opposite ends of the rockshaft connected to lift arms extending radially adjacent bearing mounts. Fore-and-aft extending links aligned with the lift arms and mounts operate lift wheel assemblies. A hitch arm connected near the center of the rockshaft is directly connected to a hitch turnbuckle for level lift operation. An aligned arrangement of cylinders, cylinder brackets, links and arms provides minimal torsional loading, particularly when the rockshaft is rotated to fully raise the implement frame for transport and is in the most susceptible shock loading condition. Moment arms are controlled to minimize rockshaft torsional loading during highest stress conditions. The front-mounted rockshaft provides simplicity and advantageous weight distribution.

대표청구항 ▼

A rockshaft is mounted over the front rank of the implement frame and is operated by cylinders located at opposite ends of the rockshaft connected to lift arms extending radially adjacent bearing mounts. Fore-and-aft extending links aligned with the lift arms and mounts operate lift wheel assemblies

A rockshaft is mounted over the front rank of the implement frame and is operated by cylinders located at opposite ends of the rockshaft connected to lift arms extending radially adjacent bearing mounts. Fore-and-aft extending links aligned with the lift arms and mounts operate lift wheel assemblies. A hitch arm connected near the center of the rockshaft is directly connected to a hitch turnbuckle for level lift operation. An aligned arrangement of cylinders, cylinder brackets, links and arms provides minimal torsional loading, particularly when the rockshaft is rotated to fully raise the implement frame for transport and is in the most susceptible shock loading condition. Moment arms are controlled to minimize rockshaft torsional loading during highest stress conditions. The front-mounted rockshaft provides simplicity and advantageous weight distribution. ve member movable relative to the frame between an open position and a closed position, the valve member being a flapper valve member that has a hinge that enables the flapper valve member to pivot relative to the frame of the valve cassette about a horizontal axis, the valve cassette having peripheral side edges with engagement means; a valve cassette receptacle positioned in the housing in a flow path of one of the first horizontal flow opening and the second horizontal flow opening and aligned with the vertical inspection and valve retrieval opening, such that at least a portion of the valve cassette can be slidably inserted in and retrieved from along a surface of the valve cassette receptacle and through the vertical inspection and retrieval opening, the valve cassette receptacle having engagement means that matingly engage the engagement means on the valve cassette; means for maintaining the valve cassette in engagement with the valve cassette receptacle until a preset vertical force is exerted; and a vertically aligned female receptacle with an internal engagement for engaging a retrieval tool positioned on the frame of the valve cassette for removal of the frame and the valve member as a single unit through the vertical inspection and retrieval opening. 8. The valve inspection chamber as defined in claim 7, wherein the engagement means on one of the valve cassette receptacle and the valve cassette is a tongue and the engagement means on an other of the valve cassette receptacle and the valve cassette is a groove. 9. The valve inspection chamber as defined in claim 8, wherein the means for maintaining the valve cassette in engagement with the valve cassette receptacle until a preset vertical force is exerted includes a projection on one of the tongue and the groove, that engages a recess in an other of the tongue and the groove. 10. The valve inspection chamber as defined in claim 7, wherein the internal engagement in the female receptacle is an internal thread which is adapted to receive an end of a rod having an external thread. 11. The valve inspection chamber as defined in claim 7, wherein the valve member is a gate valve that slides in the frame of the valve cassette on a vertical plane, and the female receptacle is positioned on top of the valve member. 12. The valve inspection chamber as defined in claim 7, wherein the valve member is a flapper valve member that has a hinge that enables the valve member to pivot relative to the frame of the valve cassette about a horizontal axis, and one of the female receptacle is positioned on the frame of valve cassette adjacent the hinge and another of the female receptacle is positioned in opposed relation opposite to the hinge, thereby enabling the valve member to be installed in either orientation. 13. The valve inspection chamber as defined in claim 7, wherein the valve cassette has a valve cassette receptacle adapted to receive a further valve cassette, thereby enabling a further valve to be installed in the housing. 14. A valve inspection chamber, comprising: a housing having a first horizontal flow opening, a second horizontal flow opening, and a vertical inspection and valve retrieval opening; a valve cassette including a frame and a valve member movable relative to the frame between an open position and a closed position, the valve cassette having peripheral side edges each of which has a projecting tongue; a valve cassette receptacle positioned in the housing in a flow path of one of the first horizontal flow opening and the second horizontal flow opening and aligned with the vertical inspection and valve retrieval opening, such that at least a portion of the valve cassette can be slidably inserted in and retrieved from along a surface of the valve cassette receptacle and through the vertical inspection and retrieval opening, the valve cassette receptacle having peripheral grooves that matingly engage mating the tongues on the valve cassette; means for ma