Workpiece storage system

• US 4,316,535 A
• Filed: 08/08/1980
• Issued: 02/23/1982
• Est. Priority Date: 05/24/1978
• Status: Expired due to Term

• Current Assignee: Unova IP Corp.
• Original Assignee: F JOS LAMB Company
• Inventors: Brems, John H., Graham, James T.
• Primary Examiner(s): Valenza, Joseph E.
• Application Number:
  US06/176,562
• Time in Patent Office: 564 Days
• Field of Search: 198/339, 198/347, 198/472, 198/473, 198/580, 198/560, 198/648, 104/89, 104/93, 104/127, 104/128, 105/148, 105/150, 188/267, 188/290
• US Class Current: 198/465.4
• CPC Class Codes: B23Q 7/1421 with a parallel disposition of working devices
• CPC Class Codes: B23Q 7/1426 with work holders not rigidly fixed to the transport devices B23Q7/005, B23Q7/035 take precedence
• CPC Class Codes: B65G 37/02 Flow-sheets for conveyor combinations in warehouses, magazines or workshops
• CPC Class Codes: B65G 47/5113 using endless conveyors B65G47/5145 takes precedence
• CPC Class Codes: B65G 47/57 for articles

Abstract

For use in a work processing line for workpieces, a workpiece storage system including a topologically closed loop track means having downwardly sloping surfaces coupled with elevators and lowerators in the loop, and work holding, gravity-operated pallets to run on said tracks having track engaging wheels equipped with retarding means responsive to wheel angular velocity and utilizing wheels of different diameters on the track depending on the loaded or unloaded condition of the pallets to control the speed of the pallets. Auxiliary track means, pallet loaders and unloaders, and switching mechanisms are incorporated in the system with elevators and lowerators to allow the storage system to function between multiple work processing lines, between single and multiple lines or between multiple and single lines to increase the flexibility of a work processing activity and reduce downtime.

Claims

1. In a series of automatic workpiece processing equipment, including individual machines, transfer machines, or individual sections of transfer machines which sequentially operate on a workpiece, thereby constituting a processing line, a gravity actuated workpiece transfer and storage system, comprising:

A. track means forming a topologically closed loop comprising a first track means having track surfaces which slope downwardly in a given topologial direction around said loop,

B. a plurality of workpiece holding pallets, each of which comprises;

1. a body adapted for supporting and holding one or more workpieces which is appropriate to said workpiece size,

2. two unpowered primary wheels of different diameters mounted on said pallet body for selectively supporting and guiding said pallet body on and with respect to said first track means,

2. retarding means acting between said pallet body and each of said primary wheels to generate a retarding torque substantially proportional to the angular velocity of said first primary wheel,

C. lifting means positioned between segments of said track means and within said topological closed loop, and adapted to raise said pallet bodies sequentially from a lower level segment of said track means to a higher level segment of said track means,

D. means for loading and unloading workpieces to and from said pallet bodies comprising a pallet body loading mechanism forming a first division which divides said track means into two portions:

a first portion for carrying empty pallet bodies and a second portion for carrying pallet bodies loaded with workpieces, and a pallet body unloading mechanism which forms a second division between said second portion and said first portion of said track means, and

E. said first and second portions of said track means being spatially related relative to said primary wheels to cause the smaller diameter primary wheel to ride on said second portion of said track means when a pallet body is loaded with a workpiece, and to cause the larger diameter primary wheel to ride on said first portion of said track when a pallet body is not loaded with a workpiece, thereby creating a different ratio of retarding force to pallet body velocity for a pallet body supported on one of said primary wheels than the ratio of retarding force to pallet body velocity for a pallet body supported on the other of said primary wheels.

3. In a series of automatic workpiece processing equipment, including individual machines, transfer machines, or individual sections of transfer machines which sequentially operate on a workpiece, thereby constituting a processing line, a gravity actuated workpiece transfer and storage system, comprising:

A. track means forming a topologically closed loop comprising inclined track surfaces which slope downwardly in a given topological direction around said loop,

B. a plurality of workpiece holding pallets, each of which comprises;

1. a body adapted for supporting and holding one or more workpieces which is appropriate to said workpiece size,

4. a plurality of unpowered axially spaced primary wheels of different diameters mounted coaxially on a common axis for selectively supporting and guiding said pallet body on and with respect to said track surfaces,retarding means acting between said pallet body and said primary wheels to generate a retarding torque substantially proportional to the angular velocity of each said primary wheel as it moves on an inclined track surface,

C. lifting means positioned between segments of said track means and within said topological closed loop, and adapted to raise said pallet bodies sequentially from a lower level segment of said track means to a higher level segment of said track means,

D. means for loading and unloading workpieces to and from said pallet bodies, comprising a pallet body loading mechanism forming a first division which divides said track means into two portions:

a first portion for carrying empty pallet bodies and a second portion for carrying pallet bodies loaded with workpieces; and

a pallet body unloading mechanism which forms a second division between said second portion and said first portion of said track means, and

E. said first and second portions of said track means being spatially related relative to said primary wheels to cause the smaller of said primary wheels to ride on the second portion of said track means when a pallet body is carrying a workpiece, and the larger of said primary wheels to ride on the first portion of said track means when a pallet body is not carrying a workpiece, thereby creating a larger ratio of retarding force to pallet body velocity for a pallet body carrying a workpiece, than the retarding force to pallet body velocity for a pallet body not carrying a workpiece.

5. In a series of automatic workpiece processing equipment, including individual machines, transfer machines, or individual sections of transfer machines which sequentially operate on a workpiece, thereby constituting a processing line, a gravity actuated workpiece transfer and storage system, comprising:

A. track means forming a topologically closed loop comprising inclined track surfaces which slope downwardly in a given topological direction around said loop,

B. a plurality of workpiece holding pallets, each of which comprises;

6. a body adapted for supporting and holding one or more workpieces which is appropriate to said workpiece size,a plurality of unpowered axially spaced primary wheels of different diameters mounted coaxially on a common axis for selectively supporting and guiding said pallet body on and with respect to said track surfaces,retarding means acting between said pallet body and said primary wheels to generate a retarding torque substantially proportional to the angular velocity of each said primary wheel as it moves on an inclined track surface,

C. lifting means positioned between segments of said track means and within said topological closed loop, and adapted to raise said pallet bodies sequentially from a lower level segment of said track means to a higher level segment of said track means,

D. means for loading and unloading workpieces to and from said pallet bodies, comprising a pallet body loading mechanism forming a first division which divides said track means into two portions:

a first portion for carrying empty pallet bodies and a second portion for carrying pallet bodies loaded with workpieces; and

a pallet body unloading mechanism which forms a second division between said second portion and said first portion of said track means, and

E. said first and second portions of said track means being laterally positioned relative to said primary wheels at said loaders, unloaders and lifting means wherein said smaller of said primary wheels engages the second portion of said track means when a pallet body is carrying a workpiece, and said larger of said primary wheels engages the first portion of said track means when a pallet body is not carrying a workpiece, thereby creating a larger ratio of retarding force to pallet body velocity for a pallet body carrying a workpiece, than the ratio of retarding force to pallet body velocity for a pallet body not carrying a workpiece.

7. In a series of automatic workpiece processing equipment, including individual machines, transfer machines, or individual sections of transfer machines which sequentially operate on a workpiece, thereby constituting a processing line, a gravity actuated workpiece transfer and storage system, comprising:

A. track means forming a topologically closed loop comprising inclined track surfaces which slope downwardly in a given topological direction around said loop,

B. a plurality of workpiece holding pallets, each of which comprises;

1. a body adapted for supporting and holding one or more workpieces which is appropriate to said workpiece size,

2. a plurality of unpowered primary wheels of different diameters mounted for selectively supporting and guiding said pallet body on and with respect to said track surfaces,

8. retarding means acting between said pallet body and said primary wheels to generate a retarding torque substantially proportional to the angular velocity of each said primary wheel as it moves on an inclined track surface,

C. lifting means positioned between segments of said track means and within said topological closed loop, and adapted to raise said pallet bodies sequentially from a lower level segment of said track means to a higher level segment of said track means,

D. means for loading and unloading workpieces to and from said pallet bodies, comprising a pallet body loading mechanism forming a first division which divides said track means into two portions:

a first portion for carrying empty pallet bodies and a second portion for carrying pallet bodies loaded with workpieces; and

a pallet body unloading mechanism which forms a second division between said second portion and said first portion of said track means, and

E. said first and second track portions having different widths to form a wider section and a narrow section, and said wheels having coaxial large and small diameter portions on each side of the centerplane of the wheels, the large diameter portions being spaced to engage the wider track sections for carrying unloaded pallets and the small diameter portions being spaced to engage the narrow track sections for carrying loaded pallets, thereby creating a larger ratio of retarding force to pallet body velocity for a pallet body carrying a workpiece, than the ratio of retarding force to pallet body velocity for a pallet body not carrying a workpiece,

F. said track portions being positioned at said loaders, unloaders and lifting means wherein said larger diameter portions of said wheels engage said wider track sections to receive and carry unloaded pallets, and said smaller diameter portions of said wheels engage the narrow track sections to receive and carry loaded pallets.

9. In a series of automatic workpiece processing equipment, including individual machines, transfer machines, or individual sections of transfer machines which sequentially operate on a workpiece, thereby constituting a processing line, a gravity actuated workpiece transfer and storage system, comprising:

A. track means forming a topologically closed loop comprising a first track means having track surfaces which slope downwardly in a given topological direction around said loop and at least one auxiliary track portion positioned along said closed loop,

B. a plurality of workpiece holding pallets, each of which comprises;

1. a body adapted for supporting and holding one or more workpieces which is appropriate to said workpiece size,

2. two unpowered primary wheels of different diameters mounted on said pallet body for selectively supporting and guiding said pallet body on and with respect to said first track means,

10. retarding means acting between said pallet body and each of said primary wheels to generate a retarding torque substantially proportional to the angular velocity of said first primary wheel,a secondary wheel mounted by free wheeling bearings on said pallet body,

C. lifting means positioned between segments of said track means and within said topological closed loop, and adapted to raise said pallet bodies sequentially from a lower level segment of said track means to a higher level segment of said track means,

D. means for loading and unloading workpieces to and from said pallet bodies comprising a pallet body loading mechanism forming a first division which divides said track means into two portions:

a first portion for carrying empty pallet bodies and a second poertion for carrying pallet bodies loaded with workpieces, and a pallet body unloading mechanism which forms a second division between said second portion and said first portion of said track means, and

E. said first and second portions of said track means being spatially related relative to said primary wheels to cause the smaller diameter primary wheel to ride on said second portion of said track means when a pallet body is loaded with a workpiece, and to cause the larger diameter primary wheel to ride on said first portion of said track when a pallet body is not loaded with a workpiece, thereby creating a different ratio of retarding force to pallet body velocity for a pallet body supported on one of said primary wheels than the ratio of retarding force to pallet body velocity for a pallet body supported on the other of said primary wheels

F. said auxiliary track portion engages said secondary wheel to support the pallets in a free-wheeling manner whereby the primary wheels do not engage said first track means.