Claims
- 1. A front end loading mechanism for a load receiving and hauling motor vehicle comprising:
- (a) a pair of lift arms pivotally mounted on the vehicle;
- (b) an arm operating system for actuating said lift arms through an arc including a lowered container receiving and releasing position, and a fully raised container emptying position;
- (c) a pair of spaced lift forks mounted to pivot relative to said lift arms;
- (d) a fork operating system for actuating and controlling the pivoting of said lift forks relative to said lift arms at a first speed including:
- (1) a double-acting fluid operated cylinder system including a pair of fork operating cylinders connected to pivot said lift forks, each having a reciprocating piston and connecting rod means and being connected to supply and drain lines for operating said forks from a relatively horizontal container engaging, releasing position through a lift segment in which the forks are rotated forward, to maintain a container in a generally upright position as the lift arms are raised, and reversing the pivot direction of said lift forks to a tip point sufficient to empty the container into said vehicle;
- (2) a storage control system enabling said forks to selectively rotate beyond said tip point to a storage point at a second speed less than said first speed and including a cylinder speed control for causing the fork operating cylinders to slow appreciably from said first speed to said second speed when the fork operating cylinders reach the position corresponding to the position of the forks at the tip point; and
- (3) wherein said cylinder speed control further includes an auxiliary fluid flow control system external to and associated with said fork operating cylinders and including a pilot-operated multi-position valve system including a flow restricting position, and wherein each of said cylinders includes a pilot port and said multi-position valve system includes a first pilot operator connected to said pilot port such that when said pistons retract beyond said pilot port, said valve system is switched into said flow-restricting position by said first pilot operator.
- 2. The mechanism of claim 1 wherein said multi-position valve system further includes a second pilot operator which prevents said multi-position valve system from restricting flow during extension of said cylinders.
- 3. The mechanism of claim 2 wherein said multi-position valve system includes an orifice meter in said flow restricting position.
- 4. The mechanism of claim 1 wherein said multi-position valve system includes an orifice meter in said flow restricting position.
- 5. A front end loading mechanism for a load receiving and hauling motor vehicle comprising:
- (a) a pair of lift arms pivotally mounted on the vehicle;
- (b) an arm operating system for actuating said lift arms through an arc including a lowered container receiving and releasing position, and a fully raised container emptying position;
- (c) a pair of spaced lift forks mounted to pivot relative to said lift arms;
- (d) a fork operating system for actuating and controlling the pivoting of said lift forks relative to said lift arms at a first speed including:
- (1) a double-acting fluid operated cylinder system including a pair of fork operating cylinders connected to pivot said lift forks, each having a reciprocating piston and connecting rod means and being connected to supply and drain lines for operating said forks from a relatively horizontal container engaging, releasing position through a lift segment in which the forks are rotated forward, to maintain a container in a generally upright position as the lift arms are raised, and reversing the pivot direction of said lift forks to a tip point sufficient to empty the container into said vehicle;
- (2) a storage control system enabling said forks to selectively rotate beyond said tip point to a storage point at a second speed less than said first speed and including a cylinder speed control for causing the fork operating cylinders to slow appreciably from said first speed to said second speed when the fork operating cylinders reach the position corresponding to the position of the forks at the tip point; and
- (3) wherein said cylinder speed control further includes an auxiliary fluid flow control system external to and associated with said fork operating cylinders and including a pilot-operated multi-position valve device mounted on each fork operating cylinder, each said multi-position valve device including a flow restricting position, a pilot port in each of said cylinders, a pilot operator in each said multi-position valve device connected to said pilot port such that when said pistons retract beyond said pilot ports, said multi-position valve devices are switched into said flow restricting position by said pilot operator.
- 6. The mechanism of claim 5 wherein said multi-position valve device further includes a second pilot operator which prevents said multi-position valve device from restricting flow during extension of said cylinders.
- 7. The mechanism of claim 6 wherein said multi-position valve device includes an orifice meter in said flow restricting position.
- 8. The mechanism of claim 5 wherein said multi-position valve device includes an orifice meter in said flow restricting position.
BACKGROUND OF THE INVENTION
This application is a Divisional Application of application Ser. No. 09/027,889, filed Feb. 23, 1998, pending.
US Referenced Citations (24)
Divisions (1)
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Number |
Date |
Country |
Parent |
027889 |
Feb 1998 |
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