RACK STORAGE SYSTEM AND METHOD FOR OPERATING IT

• US 20150336741A1
• Filed: 12/21/2012
• Published: 11/26/2015
• Est. Priority Date: 12/21/2011
• Status: Active Grant

• Current Assignee: TGW Logistics Group GmbH (Tgw Future Privatstiftung)
• Original Assignee: TGW Logistics Group GmbH (Tgw Future Privatstiftung)
• Inventors: AHAMMER, Christian, HANSL, Rudolf
• Granted Patent: US 10,173,839 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B65G 1/0485 Check-in, check-out devices
• CPC Class Codes: B65G 1/0492 with cars adapted to travel in storage aisles
• CPC Class Codes: B65G 1/065 with self propelled cars

Abstract

The invention relates to a rack storage system comprising storage racks (12a, 12b) for load (2) and a load manipulation unit (4), which has at least a first load-lifting device (34a) with a transport device (36a) and a first buffer device (35a) with transport conveying devices (43, 44) and a rack aisle (15) and guide tracks (20) extending in the rack levels in the longitudinal direction of the rack aisle (15) and single-level rack serving devices (3) for transporting load (2) as well as a conveying system being connected to the load-lifting device (34a) for transporting load (2) to and from the load-lifting device (34a). The transport conveying devices (43) each form a removing path for the load (2) and the transport conveying devices (44) each form a storing path for the load (2). In a conveying section adjacent to the load-lifting device (34a), at least one of the conveying devices (106, 107) of the conveying system also comprises a transport conveying device (108; 110) for temporarily storing one or more pieces of load (2), the transport conveying device can be approached by the conveyor vehicle (3) via guide tracks (20′) to retrieve or store load (2).

Claims

1. Rack storage system comprising

a rack storage (1) having storage racks (12a, 12b), exhibiting storage places (17) for load (2) in rack levels (16) situated one above the other, and

a load manipulation unit (4″

″

), comprising at least one first load-lifting device (34a;

84a) with a liftable and lowerable transport device (36a;

86a) for storing and retrieving load (2) as well as a first buffer device (35a;

85a) with provisioning devices (43, 44) for temporarily storing one or more pieces of load (2), and

at least one rack aisle (15) extending between adjacent storage racks (12a, 12b) and along the load-lifting device (34a;

84a) as well as the first buffer device (35a;

85a), and

guide tracks (20) running in at least some of the rack levels (16) along the rack aisle (15), and

one or more autonomous conveyor vehicles (3) displaceable along the guide tracks (20) for transporting the load (2) between the storage places (17) of the storage racks (12a, 12b) and the provisioning devices (43, 44) of the load manipulation unit (4″

″

), and

a conveying system (106a, 107a) connected to the load-lifting device (34a;

84a) for transporting load (2) to and from the load-lifting device (34a;

84a), wherein

the conveying system comprises a first conveying device (106a) for transporting load (2) to the load-lifting device (34a;

84a) and a second conveying device (107a) for transporting load (2) from the load-lifting device (34a;

84a), the first and second conveying devices (106a, 107a) are essentially arranged one above the other on a level with the corresponding rack levels (16) and extend in the extension of a storage rack (12a, 12b), and

wherein the buffer device (35a;

85a) in at least some of the rack levels (16) comprises a fixed first buffer path section (41a) and fixed second buffer path section (42a),

where the provisioning devices (43, 44) are arranged in, and

with the load-lifting device (34a;

84a) being such arranged that its transport device (36a;

86a) for storing and retrieving load (2) can be vertically positioned relative to the rack levels (16) either between two oppositely situated provisioning devices (43, 44) or in front of the front side of one of the conveying devices (106a, 107a), so that a load (2) may either be conveyed between the transport device (36a;

86a) and one of the provisioning devices (43, 44) or between the transport device (36a;

86a) and one of the conveying devices (106a, 107a), wherein

the provisioning devices (43) of the first buffer path section (41a) each form a removing path for the load (2) in each rack level (16) where they are arranged in, and the provisioning devices (44) of the second buffer path section (42a) each form a storing path for the load (2) in all rack levels (16) where they are arranged in, and wherein

in a conveying section adjacent to the load-lifting device (34a;

84a) at least one of the conveying devices (106a;

107a) also comprises a provisioning device (108;

110) for temporarily storing one or more pieces of load (2), the provisioning devices (43;

44, 108;

110) situated opposite each other on both sides of the load-lifting device (34a;

84a), and wherein

the guide tracks (20) in those rack levels (16), where the provisioning devices (43, 44) are arranged in, and the guide tracks (20′

) in at least one of the rack levels (16), where the conveying devices (106a;

107a) are disposed in, extend continuously along the rack aisle (15) and the load-lifting device (34a;

84a) as well as the provisioning devices (43, 44, 108;

110), so that in the respective rack level (16), where the provisioning devices (43, 44) are arranged in, either the provisioning device (43) in the first buffer path section (41a) or the provisioning device (44) in the second buffer path section (42a) can be approached by the conveyor vehicle (3) via the guide tracks (20) for retrieving and storing load (2), and in at least one of the rack levels (16), where the conveying devices (106a;

107a) are arranged in, either the provisioning device (43;

44) of the buffer path section (41a;

42a) or the provisioning device (108;

110) of the conveying device (106a;

107a) can be approached by the conveyor vehicle (3) via the guide tracks (20′

) for retrieving or storing load (2).

2. Rack storage system according to claim 1, wherein the first conveying device (106a) for transporting load (2) to the load-lifting device (34a;

84a) and the second conveying device (107a) for transporting load (2) from the load-lifting device (34a;

84a) of several rack aisle units or rack aisles (15) are connected to an automated distribution system (74), the distribution system (74) is adopted for transporting load (2) to and from the conveying devices (106a, 107a).

3. Rack storage system according to claim 1, wherein the rack storage (1) comprises at least one rack aisle unit which is provided in the form of adjacent storage racks (12a, 12b) and a rack aisle (15) extending between them, as well as the load manipulation unit (4′

″

″

) having a second load-lifting device (34b;

84b) having a liftable and lowerable transport device (36b;

86b) for storing and retrieving load (2) as well as a second buffer device (35b;

85b) having provisioning devices (43, 44) for temporarily buffering one or more pieces of load (2), the rack aisle (15) extending between the storage racks (12a, 12b) positioned to be adjacent to one another and along the load-lifting devices (34a;

84a, 34b;

84b) as well as the buffer devices (35a;

85a, 35b;

85b), and

the conveying system on the one hand comprises a first conveying device (106a) for transporting load (2) to the first load-lifting device (34a;

84a) and a second conveying device (107a) for transporting load (2) from the first load-lifting device (34a;

84a) and on the other hand a first conveying device (106b) for transporting load (2) to the second load-lifting device (34b;

84b) and a second conveying device (107b) for transporting load (2) from the second load-lifting device (34b;

84b), and

in at least some of the rack levels (16), the second buffer device (35b;

85b) comprises a fixed first buffer path section (41b) and a fixed second buffer path section (42b), where the provisioning devices (43, 44) are arranged in, and

the provisioning devices (43) of the first buffer path section (41b) each form a removing path for the load (2) in each rack level (16) where they are arranged in, and the provisioning devices (44) of the second buffer path section (42a) each form a storing path for the load (2) in each rack level (16) where they are arranged in, and wherein

in a conveying section adjacent to the load-lifting device (34a;

84a) at least one of the conveying devices (106b, 107b) also comprises a provisioning device (108;

110) for temporarily storing one or more pieces of load (2), the provisioning devices (43;

44, 108;

110) being situated opposite each other on both sides of the load-lifting device (34b;

84b), and wherein

the guide tracks (20) in those rack levels (16), where the provisioning devices (43, 44) are arranged in, and the guide tracks (20′

) in at least one of the rack levels (16), where the conveying devices (106b, 107b) are disposed in, extend continuously along the rack aisle (15) and the load-lifting device (34b;

84b) as well as the provisioning devices (43, 44, 108;

110), so that in the respective rack level (16), where the provisioning devices (43, 44) are arranged in, either the provisioning device (43) in the first buffer path section (41b) or the provisioning device (44) in the second buffer path section (42b) can be approached by the conveyor vehicle (3) via the guide tracks (20) for retrieving and storing load (2), and in at least one of the rack levels (16), where the conveying devices (106b;

107b) are arranged in, either the provisioning device (43;

44) of the buffer path section (41b;

42b) or the provisioning device (108;

110) of the conveying device (106b;

107b) can be approached by the conveyor vehicle (3) via the guide tracks (20′

) for retrieving or storing load (2).

4. Rack storage system according to claim 1, wherein the liftable and lowerable transport device (86a;

86b) comprises a carrying platform (87) for one or more pieces of load (2) and at least one gripping unit (90a, 90b;

91a, 91b) for relocating the load (2) between the conveying device (106a, 107a;

106b, 107b) and the transport device (86a;

86b) or between the provisioning device (43, 44) and the transport device (86a;

86b), and wherein the provisioning devices (43, 44) each form a stationary bearing table for one or more pieces of load (2) in pick up and/or transfer section (45, 46, 49, 50).

5. Rack storage system according to claim 1, wherein the liftable and lowerable transport device (86a;

86b) comprises a first gripping unit and a second gripping unit, each gripping unit comprising gripping devices (90a, 90b, 91a, 91b) which are configured for relocating load (2) and are arranged on opposite longitudinal sides (104) of the carrying platform (87) and can be adjusted relative with respect to the carrying platform (87) in both a first direction parallel with the longitudinal sides (104) and a second direction essentially perpendicular to the longitudinal sides (104),

and the transport device (86a;

86b) can be positioned in rack levels (16) between oppositely situated provisioning devices (43, 44) or in one of the rack levels (16) between the provisioning device (43;

44) and a conveying device (106a, 106b, 107a, 107b) opposite the latter, and the first gripping unit and/or the second gripping unit can be such controlled that at least a first load (2) and at least a second load (2) can be simultaneously moved by means of the first gripping unit and the second gripping unit, either between the transport device (86a;

86b) and the transfer and/or pick-up sections (46, 49) of the provisioning device (43, 44) or between the transport device (86a;

86b) and one of the conveying devices (106a, 106b, 107a, 107b).

6. Rack storage system according to claim 4, wherein the liftable and lowerable transport device (86a;

86b) for one or more pieces of load (2) additionally comprises one or more conveying devices (88, 89) arranged one behind the other in conveying direction.

7. Rack storage system according to claim 1, wherein the provisioning devices (43, 44) are each provided in the form of transport conveying devices and between which the transport device (36a;

36b) of the load-lifting device (34a;

34b) may be positioned and such driven that it is possible that at least a first load (2) is being conveyed from the first buffer path section (41a;

41b) onto the transport device (36a, 36b) at the same time when at least a second load (2) is being conveyed from the transport device (36a;

36b) onto the second buffer path section (42a;

42b).

8. Rack storage system according to claim 7, wherein the transport conveying devices (43) in the first buffer path section (41a;

41b) are provided in the form of accumulating tracks conveying the load (2) from a pick-up section (45) remote from the load-lifting device (34a;

34b) to a transfer section (46) adjacent to the load-lifting device (34a;

34b) in one single conveying direction (48a;

48b), and the pick-up section (45) can be approached by the single-level rack serving device (3) and a load (2) can be relocated from the single-level rack serving device (3) to the pick-up section (45).

9. Rack storage system according to claim 7, wherein the transport conveying devices (44) in the second buffer path section (42a;

42b) can be provided in the form of accumulating tracks conveying the load (2) from a pick-up section (49) adjacent to the load-lifting device (34a;

34b) to a transfer section (50) remote from the load-lifting device (34a;

34b) in one single conveying direction (52a;

52b), and the transfer section (50) can be approached by the single-level rack serving device (3) and a load (2) can be relocated from the transfer section (50) to the single-level rack serving device (3).

10. Rack storage system according to claim 8, wherein the accumulating tracks form at least one buffer section (47;

51) each situated between the pick-up place (45;

49) and the transfer place (46;

50).

11. Rack storage system according to claim 1, wherein the load-lifting devices (34a;

34b;

84a, 84b) are positioned at a distance at least corresponding to the width of an aisle and are arranged to be laterally reversed.

12. Rack storage system according to claim 1, wherein the load-lifting devices (34a;

34b;

84a, 84b) are positioned at a distance at least corresponding to the width of an aisle and are arranged to be axially offset.

13. Rack storage system according to claim 1, wherein the load manipulation unit (4″

″

;

4′

″

″

) is arranged at the front ends of the storage racks (12a, 12b).

14. Rack storage system according to claim 1, wherein the load manipulation unit (4″

″

;

4′

″

″

) is integrated in the storage racks (12a, 12b).

15. Rack storage system comprising

a rack storage (1) having storage racks (12a, 12b), exhibiting storage places (17) for load (2) in rack levels (16) situated one above the other, and

a load manipulation unit (4;

4′

;

4″

, 4′

″

), comprising at least one first load-lifting device (34a;

84a) with a liftable and lowerable transport device (36a;

86a) for storing and retrieving load (2) as well as a first buffer device (35a;

85a) with provisioning devices (43, 44) for temporarily storing one or more pieces of load (2), and

at least one rack aisle (15;

15.1, 15.2) extending between adjacent storage racks (12a, 12b) and along the load-lifting device (34a;

84a) as well as the first buffer device (35a;

85a), and

guide tracks (20) running in at least some of the rack levels (16) along the rack aisle (15;

15.1, 15.2), and

one or more autonomous conveyor vehicles (3) displaceable along the guide tracks (20) for transporting the load (2) between the storage places (17) of the storage racks (12a, 12b) and the provisioning devices (43, 44) of the load manipulation unit (4;

4′

;

4″

;

4′

″

), and

a conveying system (54a, 55a;

69, 71) connected to the load-lifting device (34a;

84a) for transporting load (2) to and from the load-lifting device (34a;

84a), and

the conveying system comprising a first conveying device (54a;

69) for transporting load (2) to the load-lifting device (34a;

84a) and a second conveying device (55a;

71) for transporting load (2) from the load-lifting device (34a;

84a), the first and second conveying device (54a, 107a) are located opposite each other, and

in at least some of the rack levels (16), the buffer device (35a;

85a) comprises a fixed first buffer path section (41a) and fixed second buffer path section (42a), where the provisioning devices (43, 44) are arranged in, and

wherein the load-lifting device (34a;

84a) is arranged between the buffer path sections (41a, 42a) and the conveying devices (54a, 55a;

69, 71) in such a way that the transport device (36a;

86a) for storing and retrieving load (2) can be vertically positioned relative to the rack levels (16) either between two oppositely situated provisioning devices (43, 44) or between the conveying devices (54a, 55a;

69, 71), so that a load (2) may either be conveyed between the transport device (36a;

86a) and one of the provisioning devices (43, 44) or between the transport device (36a;

86a) and one of the conveying devices (54a, 55a;

69, 71),

wherein

in those rack levels (16) where the provisioning devices (43, 44) are arranged in, the guide tracks (20) extend continuously along the rack aisle (15;

15.1, 15.2) and the load-lifting device (34a;

84a) as well as the provisioning devices (43, 44), and

the first buffer path section (41a) with the provisioning devices (43) and the second buffer path section (42a) with the provisioning devices (44) as well as the load-lifting device (34a;

84a), which is arranged between the conveying devices (54a, 55a;

69, 71) and the buffer path sections (41a, 42a) and has the liftable and lowerable transport device (36a;

86a) for storing and retrieving load (2), are provided sideways next to the rack aisle (15;

15.1, 15.2) along the guide tracks (20) so that in the respective rack level (16), either the provisioning device (43) in the first buffer path section (41a) or the provisioning device (44) in the second buffer path section (42a) can be approached by the conveyor vehicle (3) via the guide tracks (20) for retrieving and storing load (2) and

wherein the provisioning devices (43) of the first buffer path section (41a) each form a removing path for the load (2) in each rack level (16) where they are arranged in, and the provisioning devices (44) of the second buffer path section (42a) each form a storing path for the load (2) in all rack levels (16) where they are arranged in.

16. Rack storage system according to claim 15, wherein the first conveying device (54a;

69) for transporting load (2) to the load-lifting device (34a;

84a) and the second conveying device (55a;

71) for transporting load (2) from the load-lifting device (34a;

84a) of several rack aisles (15.1, 15.2) are connected to an automated distribution system (74), the distribution system (74) is adopted for transporting load (2) to and from the conveying devices (54a, 55a).

17. Rack storage system according to claim 15, wherein the first conveying device (54a;

69) and the second conveying device (55a;

71) form conveying sections (75, 76) running parallel with the rack aisle (15;

15.1, 15.2) and aligned facing each other, as well as one of the conveying devices (54a;

69;

55a;

71) forms a second conveying section (77) and a third conveying section (78) running parallel with the rack aisle (15;

15.1, 15.2), and the first and the third conveying section (75, 78) are offset to each other within a conveying system plane (56), or the first and the third conveying section (75, 78) are arranged in conveying system planes (56, 57) positioned one above the other, the first and the third conveying section (75, 78) being connected via the second conveying section (77).

18. Rack storage system according to claim 17, wherein the rack storage (1) comprises at least two rack aisle units, each rack aisle unit of which being provided in the form of adjacent storage racks (12a, 12b) and a rack aisle (15.1, 15.2) extending between the latter as well as comprising the load manipulation unit (4;

4′

;

4″

;

4′

″

), and wherein the first conveying sections (75, 76) of the conveying devices (54a, 55a;

54b, 55b;

69, 71) extend in the extension of a storage rack (12a, 12b) of the first rack aisle unit and the third conveying section (78) of the conveying device (54a, 55a;

54b, 55b;

69, 71 extends in the extension of a storage rack (12a, 12b) of the second rack aisle unit.

19. Rack storage system according to claim 17, wherein the rack storage (1) comprises at least two rack aisle units, each rack aisle unit of which being provided in the form of adjacent storage racks (12a, 12b) and a rack aisle (15.1, 15.2) extending between the latter as well as comprising the load manipulation unit (4;

4′

;

4″

;

4′

″

), the rack aisle units being arranged at a mutual distance, so that an aisle (79) is formed between the adjacent storage racks (12a, 12b) of the rack aisle units, in the extension of which aisle or within which aisle a part of the third conveying section (78) extends.

20. Rack storage system according to claim 15, wherein the rack storage (1) comprises at least one rack aisle unit, which is provided in the form of adjacent storage racks (12a, 12b) and a rack aisle (15) extending between the latter as well as comprises the load manipulation unit (4″

), and wherein the first conveying sections (75, 76) of the conveying devices (69, 71) extend in the extension of a storage rack (12a, 12b) of the rack aisle unit and the third conveying section (78) of the conveying device (69;

71) extends in the extension of the rack aisle (15;

15.1, 15.2).

21. Rack storage system according to claim 15, wherein the rack storage (1) comprises at least one rack aisle unit which is provided in the form of adjacent storage racks (12a, 12b) and a rack aisle (15;

15.1, 15.2) extending between the latter as well as the load manipulation unit (4′

;

4″

), the load manipulation unit (4′

;

4″

) having a second load-lifting device (34b;

84b) with a liftable and lowerable transport device (36b;

86b) for storing and retrieving load (2) as well as a second buffer device (35b;

85b) with provisioning devices (43, 44) for temporarily storing one or more pieces of load (2), the rack aisle (15;

15.1, 15.2) extending between the adjacent storage racks (12a, 12b) and along the load-lifting devices (34a;

84a, 34b;

84b) as well as the buffer devices (35a;

85a, 35b;

85b), and

the conveying system comprises on the one hand a first conveying device (54a;

69) for transporting load (2) to the first load-lifting device (34a;

84a) and a second conveying device (55a;

71) for transporting load (2) from the first load-lifting device (34a;

84a) and on the other hand a first conveying device (54b;

69) for transporting load (2) to the second load-lifting device (34b;

84b) and a second conveying device (55b;

71) for transporting load (2) from the second load-lifting device (34b;

84b), and

in at least some of the rack levels (16), the second buffer device (35b;

85b) comprises a fixed first buffer path section (41b) and a fixed second buffer path section (42b), where the provisioning devices (43, 44) are arranged in, and

the load-lifting device (34b;

84b) is arranged between the buffer path sections (41a, 42a) and the conveying devices (54a, 55a, 54b, 55b;

69, 71) in such a way that the transport device (36b;

86b) for storing and retrieving load (2) can be vertically positioned relative to the rack levels (16) either between two oppositely situated provisioning devices (43, 44) or between the conveying devices (54a, 55a, 54b, 55b;

69, 71), so that a load (2) may either be conveyed between the transport device (36b;

86b) and one of the provisioning devices (43, 44) or between the transport device (36b;

86b) and one of the conveying devices (54a, 55a, 54b, 55b;

69, 71), and

the first and the second conveying devices (54a, 55a, 54b, 55b;

69, 71) each form first conveying sections (75, 76) extending in the extension of the storage racks (12a, 12b) and aligned facing each other, and a common third conveying section (78) in the extension of the rack aisle (15;

15.1, 15.2), and one of the conveying devices (54a, 55a, 54b, 55b;

69, 71) forms a second conveying section (77), and

the first conveying sections (75, 76) of the first conveying devices (54a, 54b, 69) or the second conveying devices (55a, 55b;

71) are connected with the third conveying section (78) via the second conveying section (77).

22. Rack storage system according to claim 15, wherein the conveying system (54a;

54b;

69;

55a;

55b;

69, 71) for transporting load (2) to and from the load-lifting device (34a;

84a;

34a;

84a, 34b;

84b) comprises at least one transfer and pick-up device (80) for one or more pieces of load (2), the transfer and pick-up device (80) directly following the first conveying device (54a;

54b;

69) and/or second conveying device (55a;

55b;

71) of the conveying system (54a;

54b;

69;

55a;

55b;

69, 71), and wherein the guide tracks (20) in that rack level (16), where the conveying system (54a;

54b;

69;

55a;

55b;

69, 71) for transporting load (2) to and from the load-lifting device (34a;

84a;

34b;

84b) is arranged in, extends along the transfer and pick-up device (80), and the transfer and pick-up device (80) can be approached by the conveyor vehicle (3) by means of the guide track (20), so that load (2) to be retrieved or stored can be conveyed between the conveyor vehicle (3) and the transfer and pick-up device (80).

23. Rack storage system according to claim 15, wherein the liftable and lowerable transport device (86a;

86b) comprises a carrying platform (87) for one or more pieces of load (2) and at least one gripping unit (90a, 90b;

91a, 91b) for relocating the load (2) between the conveying devices (54a, 55a;

54b, 55b;

69, 71) and the transport device (86a;

86b) or between the provisioning devices (43, 44) and the transport device (86a;

86b), and wherein the provisioning devices (43, 44) each form a stationary bearing table for one or more pieces of load (2) in pick up and/or transfer section (45, 46, 49, 50).

24. Rack storage system according to claim 15, wherein the liftable and lowerable transport device (86a;

86b) comprises a first gripping unit and a second gripping unit, each gripping unit comprising gripping devices (90a, 90b, 91a, 91b) which are configured for relocating load (2) and are arranged on opposite longitudinal sides (104) of the carrying platform (87) and can be adjusted relative with respect to the carrying platform (87) in both a first direction parallel with the longitudinal sides (104) and a second direction essentially perpendicular to the longitudinal sides (104),

and at least a first load (2) can be moved by means of the first gripping unit either from one of the pick-up and/or transfer sections (45, 46) in the first buffer path section (41a;

41b) or from the first conveying system (54a;

54b;

69) for transporting load (2) to the transport device (86a;

86b) and

at least a second load (2) can be moved by means of the second gripping unit from the transport device (86a;

86b) either onto one of the pick-up and/or transfer sections (49, 50) in the second buffer path section (42a;

42b) or onto the second conveying system (55a;

55b;

71) for retrieving load (2) simultaneously.

25. Rack storage system according to claim 23, wherein the liftable and lowerable transport device (86a;

86b) for one or more pieces of load (2) additionally comprises one or more conveying devices (88, 89) arranged one behind the other in conveying direction.

26. Rack storage system according to claim 15, wherein the provisioning devices (43, 44) are each provided in the form of transport conveying devices and between which the transport device (36a;

36b) of the load-lifting device (34a;

34b) may be positioned and such driven that it is possible that at least a first load (2) is being conveyed from the first buffer path section (41a;

41b) onto the transport device (36a, 36b) and at the same time at least a second load (2) is being conveyed from the transport device (36a;

36b) onto the second buffer path section (42a;

42b).

27. Rack storage system according to claim 26, wherein the transport conveying devices (43) in the first buffer path section (41a;

41b) are provided in the form of accumulating tracks conveying the load (2) from a pick-up section (45) remote from the load-lifting device (34a;

34b) to a transfer section (46) adjacent to the load-lifting device (34a;

34b) in one single conveying direction (48a;

48b), and the pick-up section (45) can be approached by the single-level rack serving device (3) and a load (2) can be relocated from the single-level rack serving device (3) to the pick-up section (45).

28. Rack storage system according to claim 26, wherein the transport conveying devices (44) in the second buffer path section (42a;

42b) can be provided in the form of accumulating tracks conveying the load (2) from a pick-up section (49) adjacent to the load-lifting device (34a;

34b) to a transfer section (50) remote from the load-lifting device (34a;

34b) in one single conveying direction (52a;

52b), and the transfer section (50) can be approached by the single-level rack serving device (3) and a load (2) can be relocated from the transfer section (50) to the single-level rack serving device (3).

29. Rack storage system according to claim 27, wherein the accumulating tracks form at least one buffer section (47;

51) each positioned between the pick-up place (45;

49) and the transfer place (46;

50).

30. Rack storage system according to claim 15, wherein the load-lifting devices (34a;

34b;

84a, 84b) are positioned at a distance at least corresponding to the width of an aisle and are arranged to be laterally reversed.

31. Rack storage system according to claim 15, wherein the load-lifting devices (34a;

34b;

84a, 84b) are positioned at a distance at least corresponding to the width of an aisle and are arranged to be axially offset.

32. Rack storage system according to claim 26, wherein the conveying system comprises a first conveying device (54a;

54b;

69) connected to the load-lifting device (34a;

34b) for transporting load (2) to the load-lifting device (34a;

34b), and a second conveying device (55a;

55b;

71) for transporting load (2) from the load-lifting device (34a;

34b), and the transport device (36a;

36b) of the load-lifting device (34a;

34b) can be such positioned between the conveying devices (54a;

54b;

55a;

55b;

69, 71) aligned facing each other and such driven that conveying at least a first load (2) from the first conveying device (54a;

54b;

69) onto the transport device (36a;

36b) and conveying at least a second load (2) from the transport device (36a;

36b) onto the second conveying device (55a;

55b;

71) can take place simultaneously.

33. Rack storage system according to claim 15, wherein the first conveying device (54a;

54b) for transporting load (3) to the load-lifting device (34a;

34b) comprises conveying sections (58, 59) which extend in conveying system planes (56, 57) arranged one above the other and parallel with the rack aisle (15), and which are connected to one another via a transfer lifter (60).

34. Rack storage system according to claim 15, wherein the conveying system comprises a first conveying device (69) connected to the respective load-lifting device (34a;

34b) for transporting load (2) to the load-lifting device 34a;

34b), and a second transport device (71) for transporting load (2) from the load-lifting device (34a;

34b), and a processing track (65) running in the rack aisle (15), as well as a delivery device (67) for transporting load (2) from the processing track (66) onto the first conveying device (69).

35. Rack storage system according to claim 15, wherein the load manipulation unit (4;

4′

;

4″

;

4′

″

) is arranged at the front ends of the storage racks (12a, 12b).

36. Rack storage system according to claim 15, wherein the load manipulation unit (4;

4′

;

4″

;

4′

″

) is integrated in the storage racks (12a, 12b).

37. Rack storage system according to claim 21, wherein the first conveying device (54a;

69) for transporting load (2) to the first load-lifting device (34a) and the second conveying device (55a;

71) for transporting load (2) from the first load-lifting device (34a) are connected to a first workstation and the first conveying device (54b;

69) for transporting load (2) to the second load-lifting device (34b) and the second conveying device (55b;

71) for transporting load (2) from the second load-lifting device (34b) are connected to a second workstation.

38. Method for operating a rack storage system embodied according to claim 15, wherein at least in some of the rack levels (16), the transport device (36a;

36b) of the load-lifting device (34a;

34b) is such positioned between a first buffer path section (41a;

41b) and a second buffer path section (42a;

42b) that the movement and/or conveying of a first load (2) from the first buffer path section (41a;

41b) onto the transport device (36a;

36b) and of a second load (2) from the transport device (36a;

36b) onto the second buffer path section (42a;

42b) is carried out simultaneously.

39. Method according to claim 38, wherein the first load (2) is conveyed by the single-level rack serving device (3) from a storage place (17) to a pick-up section (45) which is in the first buffer path section (41a;

41b) on the transport conveying device (43) and remote from the load-lifting device (34a;

34b), and from the pick-up section (45) in conveying direction (48a;

48b) to a transfer section (46) adjacent to load-lifting device (34a;

34b).

40. Method according to claim 38, wherein the second load (2) is conveyed by the transport device (36a, 36b) to a pick-up section (49) adjacent to the load-lifting device (34a;

34b) from where it is conveyed in conveying direction (52a;

52b) to a transfer section (50) remote from the load-lifting device on the transport conveying device (44) in the second buffer path section (42a;

42b), and afterwards picked up from the pick-up section (49 by the single-level rack serving device (3) and conveyed to a storage place (17).

43. Rack storage system comprising storage racks (12a, 12b), exhibiting storage places (17) for load (2) in rack levels (16) arranged one above the other, and a load manipulation unit (4;

4′

;

4″

) which has at least one first load-lifting device (34a) with a transport device (36a) and a first buffer device (35a) having transport conveying devices (43, 44), and at least one rack aisle (15) extending between the storage racks (12a, 12b) and along the load-lifting device (34a) as well as buffer device (35a), and guide tracks (20) extending in longitudinal direction of the rack aisle (15), in at least some of the rack levels (16), and at least one single-level rack serving device (3) displaceable along the guide tracks (15) for transporting load (2) between the storage places (17) in the storage racks (12a, 12b) and the buffer device (35a) in the load manipulation unit (4;

4′

;

4″

) as well as a conveying system (54a, 55a;

69, 71) connected to the load-lifting device (34a) for transporting load (2) to and from the load-lifting device (34a), wherein in at least some of the rack levels (16), the buffer device (35a) comprises a stationary first buffer path section (41a) and second buffer path section (42a), where the transport conveying devices (43, 44) are arranged in and between which the transport device (36a) of the load-lifting device (34a) can be vertically positioned, and wherein in each rack level (16) where they are arranged in, the transport conveying devices (43, 44) of the first buffer device (35a) each comprise a accumulating track conveying the load (2) at only one (non-reversible) and in the same conveying direction (48a, 52a), wherein the rack storage system is embodied according to claim 15.

41. Rack storage system comprising storage racks (12a, 12b), exhibiting storage places (17) for load (2) in rack levels (16) arranged one above the other, and a load manipulation unit (4;

4′

;

4″

) which has at least one first load-lifting device (34a) with a transport device (36a) and a first buffer device (35a) having transport conveying devices (43, 44), and at least one rack aisle (15) extending between the storage racks (12a, 12b) and along the load-lifting device (34a) as well as buffer device (35a), and guide tracks (20) extending in longitudinal direction of the rack aisle (15), in at least some of the rack levels (16), and at least one single-level rack serving device (3) displaceable along the guide tracks (15) for transporting load (2) between the storage places (17) in the storage racks (12a, 12b) and the buffer device (35a) in the load manipulation unit (4;

4′

;

4″

) as well as a conveying system (54a, 55a;

69, 71) connected to the load-lifting device (34a) for transporting load (2) to and from the load-lifting device (34a), wherein in at least some of the rack levels (16), the buffer device (35a) comprises a stationary first buffer path section (41a) and second buffer path section (42a), where the transport conveying devices (43, 44) are arranged in and between which the transport device (36a) of the load-lifting device (34a) can be vertically positioned, and wherein in each rack level (16) where they are arranged in, the transport conveying devices (43, 44) of the first buffer device (35a) each comprise a accumulating track conveying the load (2) at only one (non-reversible) and in the same conveying direction (48a, 52a).

42. Rack storage system according to claim 41, wherein the load manipulation unit (4′

, 4″

) further has a second load-lifting device (34b) with a transport device (36b) and a second buffer device (35b) with transport conveying devices (43, 44), which is arranged along the rack aisle (15), and a conveying system (54b, 55b;

69, 71) for transporting load (2) to and from the load-lifting device (34b) is connected to the second load-lifting device (34b), and at least in some of the rack levels (16) the buffer device (35b) comprises a stationary first buffer path section (41b) and a stationary second buffer path section (42b), where the transport conveying devices (43, 44) are arranged in and between which the transport device (36b) of the load-lifting device (34b) can be vertically positioned, and wherein in each rack level (16) where they are arranged in, the transport conveying devices (43, 44) of the second buffer device (36b) each comprise an accumulating track conveying the load (2) at only one (non-reversible) and in the same conveying direction (48a, 52a).

44. Method for operating a rack storage system according to claim 41, wherein in at least some of the rack levels (16) the transport device (36a;

36b) of the load-lifting device (34a;

34b) is positioned between a first buffer path section (41a;

41b) and a second buffer path section (42a;

42b) and wherein in each rack level (16) where they are arranged in, the transport conveying devices (43, 44) of the first buffer device (35a) are operated at only one (non-reversible) and the same conveying direction (48a;

48b;

52a;

52b), so that the load (2) on the first transport conveying devices (43) is conveyed in direction (48a;

48b) towards the load-lifting device (34a;

34b) and the load (2) on the second transport conveying devices (44) is conveyed in direction (52a;

52) away from the load-lifting device (34a;

34b).

45. Method according to claim 44, wherein at least in some of the rack levels (16), the transport device (36a;

36b) of the load-lifting device (34a;

34b) is such positioned between a first buffer path section (41a;

41b) and a second buffer path section (42a;

42b) that the movement and/or conveying of a first load (2) from the first buffer path section (41a;

41b) onto the transport device (36a;

36b) and of a second load (2) from the transport device (36a;

36b) onto the second buffer path section (42a;

42b) is carried out simultaneously.