阅读说明：本技术 货叉组件及叉车 (Fork subassembly and fork truck ) 是由 韩继峰 李发旺 于 2018-06-29 设计创作，主要内容包括：本发明属于叉车技术领域,涉及一种货叉组件及叉车。该货叉组件包括叉架、支承导轨、驱动组件以及货叉,所述叉架包括前部托架,所述支承导轨沿叉车的左右方向固定连接在所述前部托架上,所述货叉滑动连接在所述支承导轨上,所述驱动组件用于驱动所述货叉沿所述支承导轨往复滑动。该货叉组件的货叉沿支承导轨滑动时能够伸出前部托架的左右两侧边沿,从而伸进货架上的托盘叉孔内装卸货物,实现对巷道左右两侧的货架上的货物的装卸。(The invention belongs to the technical field of forklifts, and relates to a fork assembly and a forklift. The fork assembly comprises a fork frame, a supporting guide rail, a driving assembly and a fork, wherein the fork frame comprises a front bracket, the supporting guide rail is fixedly connected to the front bracket along the left-right direction of the forklift, the fork is connected to the supporting guide rail in a sliding mode, and the driving assembly is used for driving the fork to slide back and forth along the supporting guide rail. The fork of the fork assembly can stretch out the left and right side edges of the front bracket when sliding along the supporting guide rail, so that the fork assembly can stretch into the tray fork holes on the goods shelf to load and unload goods, and the goods on the goods shelves on the left and right sides of the roadway can be loaded and unloaded.)

1. A fork assembly for a fork lift truck comprising a fork carriage including a forward carriage, a support rail fixedly attached to the forward carriage in a left-right direction of the fork lift truck, a drive assembly slidably attached to the support rail, and a fork, the drive assembly being adapted to drive the fork to slide reciprocally along the support rail.

2. The fork assembly of claim 1, wherein the drive assembly comprises a power device, a primary moving frame and a secondary moving frame, the power device is fixedly connected to the front bracket, the primary moving frame is slidably disposed on the front bracket, the power device is configured to drive the primary moving frame to slide back and forth along the left and right directions of the forklift, a primary gear is disposed on the primary moving frame, and the primary gear is rotatably connected to the primary moving frame;

a first rack is fixedly connected to the front bracket;

the second-stage moving frame comprises a moving plate and a second rack, the second rack is fixed to the bottom of the moving plate, the first-stage gear is meshed with the first rack and the second rack simultaneously, and the fork is linked with the moving plate.

3. The fork assembly of claim 2, wherein a third rack is further fixedly attached to the front bracket, and a fourth rack is provided on a side wall of the fork;

the second-stage moving frame further comprises a duplicate gear, the duplicate gear comprises a pinion and a bull gear which are coaxially connected, the pinion is meshed with the third rack, and the bull gear is meshed with the fourth rack.

4. The fork assembly of claim 3, wherein the second rack is positioned above the first rack and the fourth rack is positioned above the third rack.

5. The pallet fork assembly of claim 2, wherein the power device is a cylinder, a piston rod of the cylinder is parallel to the support rail, and the primary moving frame is fixedly connected to the piston rod of the cylinder.

6. The fork assembly of any one of claims 2-5, wherein the fork comprises an inner fork and an outer fork slidably coupled to an outer side of the inner fork, the inner fork slidably coupled to the support rail.

7. The pallet fork assembly of claim 6, wherein the support rail is provided with a first roller and a first nylon slider on both front and rear sides;

the inner fork is provided with a T-shaped groove with an opening at the lower end, the first roller is in rolling contact with the T-shaped groove, and the first nylon sliding block is in sliding contact with the T-shaped groove.

8. The pallet fork assembly of claim 7, wherein the inner fork is provided with a first chain groove and a second chain groove arranged along the left-right direction of the forklift, the left end of the first chain groove is provided with a first through hole, and the right end of the second chain groove is provided with a second through hole;

the pallet fork also comprises a first chain wheel, a first chain wheel shaft, a second chain wheel shaft, a first chain and a second chain, the first chain wheel shaft is fixed in the first through hole along the front-back direction of the forklift, the first chain wheel is rotationally connected to the first chain wheel shaft, the second chain wheel shaft is fixed in the second through hole along the front-back direction of the forklift, the second chain wheel is rotationally connected to the second chain wheel shaft, the first chain is wound on the first chain wheel, one end of the first chain is fixedly connected to the inner side wall of the top plate of the outer fork, the other end of the first chain is fixedly connected to the supporting guide rail, the second chain is wound on the second chain wheel, one end of the second chain is fixedly connected to the inner side wall of the top plate of the outer fork, and the other end of the second chain is fixedly connected to the supporting guide rail.

9. The fork assembly of claim 8, wherein the first chain groove includes a first sub groove and a second sub groove symmetrically disposed on upper and lower sides of the inner fork, the second chain groove includes a third sub groove and a fourth sub groove symmetrically disposed on upper and lower sides of the inner fork, an upper end opening of the first through hole communicates with the first sub groove, a lower end opening of the first through hole communicates with the second sub groove, an upper end opening of the second through hole communicates with the third sub groove, and a lower end opening of the second through hole communicates with the fourth sub groove.

10. The fork assembly of claim 8, wherein the top plate of the outer fork has fixedly attached to an inner sidewall thereof a first chain mount and a second chain mount, wherein one end of the first chain is fixedly attached to the first chain mount and one end of the second chain is fixedly attached to the second chain mount.

11. The fork assembly of claim 8, further comprising a first chain tensioner fixedly attached to the left end of the support rail and a second chain tensioner fixedly attached to the right end of the support rail, wherein the other end of the first chain is fixedly attached to the first chain tensioner and the other end of the second chain is fixedly attached to the second chain tensioner.

12. The pallet fork assembly of claim 6, wherein the front and rear sides of the outer fork are provided with a second roller and a second nylon slider;

an inwards-concave sliding groove is formed in the side wall of the inner fork, the second roller is in rolling contact with the inside of the sliding groove, and the second nylon sliding block is in sliding contact with the inside of the sliding groove.

13. The fork assembly of any one of claims 2-5, further comprising a travel switch fixedly attached to the support rail.

14. The fork assembly of any of claims 2-5, further comprising cameras fixedly attached to the left and right sides of the support rail.

15. A forklift truck comprising a fork assembly as claimed in any one of claims 1 to 14.

Technical Field

The invention belongs to the technical field of forklifts, and particularly relates to a fork assembly and a forklift.

Background

The warehouse operation fork truck of present mainstream generally divide into counter weight formula fork truck, antedisplacement fork truck, stack fork truck, select fork truck and side fork truck etc, except selecting outside fork truck and the side fork truck, other types of fork truck are equipped with forward fork truck (relative fork truck direction of advance), fork truck need turn over 90 when the operation in goods shelves warehouse, during the operation in narrow tunnel, it is more difficult when loading and unloading the goods on the goods shelves of both sides, need the passageway width of broad, general passageway width need be greater than 3.5m, this effective volume ratio and the utilization ratio that has also greatly reduced the warehouse. If the three-way rotary pallet fork is used, three-way operation can be realized, but the front suspension distance is large when the three-way rotary pallet fork rotates to the front, so that the bearing capacity of the forklift is greatly reduced, and the forklift is low in efficiency and unsafe. If a side forklift is used, only one side operation can be performed frequently, but the side forklift is large in general appearance, is inconvenient to bend or turn around in a narrow space of a warehouse, and also has the problems of inconvenience in loading and unloading and low working efficiency.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: to the technical problem that current side fork truck can only carry out one side operation, provide a fork subassembly and fork truck.

In order to solve the above technical problems, in one aspect, an embodiment of the present invention provides a fork assembly including a fork carriage, a support rail, a driving assembly, and a fork, wherein the fork carriage includes a front bracket, the support rail is fixedly connected to the front bracket along a left-right direction of a forklift, the fork is slidably connected to the support rail, and the driving assembly is configured to drive the fork to slide back and forth along the support rail.

According to the fork assembly provided by the embodiment of the invention, the supporting guide rail is fixedly connected to the front bracket of the forklift along the left and right directions of the forklift, the fork is connected to the supporting guide rail in a sliding manner, the driving assembly drives the fork to slide along the supporting guide rail in a reciprocating manner, and the fork can extend out of the left and right side edges of the front bracket when sliding along the supporting guide rail, so that the fork extends into the tray fork holes in the goods shelf to load and unload goods, and the goods on the goods shelves on the left and right sides of a roadway are loaded and unloaded. The forklift provided with the fork assembly does not need to turn 90 degrees in a roadway, and goods on goods shelves at two sides can be loaded and unloaded in the driving process of the roadway, so that the operation capacity of the forklift in a narrow-passage goods shelf warehouse is improved, and the operation efficiency of the forklift is also improved. In addition, the minimum channel width of the roadway can be greatly reduced, the volume ratio and the storage capacity of the warehouse are improved, the area of the warehouse can be saved, the land can be saved, and the economic benefit and the social benefit are remarkable.

Optionally, the driving assembly comprises a power device, a primary moving frame and a secondary moving frame, the power device is fixedly connected to the front bracket, the primary moving frame is arranged on the front bracket in a sliding manner, the power device is used for driving the primary moving frame to slide in a reciprocating manner along the left and right directions of the forklift, a primary gear is arranged on the primary moving frame, and the primary gear is rotatably connected to the primary moving frame;

a first rack is fixedly connected to the front bracket;

the second-stage moving frame comprises a moving plate and a second rack, the second rack is fixed to the bottom of the moving plate, the first-stage gear is meshed with the first rack and the second rack simultaneously, and the fork is linked with the moving plate.

Optionally, a third rack is further fixedly connected to the front bracket, and a fourth rack is arranged on the side wall of the fork;

the second-stage moving frame further comprises a duplicate gear, the duplicate gear comprises a pinion and a bull gear which are coaxially connected, the pinion is meshed with the third rack, and the bull gear is meshed with the fourth rack.

Optionally, the second rack is located above the first rack, and the fourth rack is located above the third rack.

Optionally, the power device is an oil cylinder, a piston rod of the oil cylinder is parallel to the supporting guide rail, and the primary moving frame is fixedly connected with the piston rod of the oil cylinder.

Optionally, the pallet fork comprises an inner fork and an outer fork slidably connected to an outer side of the inner fork, the inner fork being slidably connected to the support rail.

Optionally, a first roller and a first nylon sliding block are arranged on the front side and the rear side of the supporting guide rail;

the inner fork is provided with a T-shaped groove with an opening at the lower end, the first roller is in rolling contact with the T-shaped groove, and the first nylon sliding block is in sliding contact with the T-shaped groove.

Optionally, the inner fork is provided with a first chain groove and a second chain groove which are arranged along the left-right direction of the forklift, the left end of the first chain groove is provided with a first through hole, and the right end of the second chain groove is provided with a second through hole;

the pallet fork also comprises a first chain wheel, a first chain wheel shaft, a second chain wheel shaft, a first chain and a second chain, the first chain wheel shaft is fixed in the first through hole along the front-back direction of the forklift, the first chain wheel is rotationally connected to the first chain wheel shaft, the second chain wheel shaft is fixed in the second through hole along the front-back direction of the forklift, the second chain wheel is rotationally connected to the second chain wheel shaft, the first chain is wound on the first chain wheel, one end of the first chain is fixedly connected to the inner side wall of the top plate of the outer fork, the other end of the first chain is fixedly connected to the supporting guide rail, the second chain is wound on the second chain wheel, one end of the second chain is fixedly connected to the inner side wall of the top plate of the outer fork, and the other end of the second chain is fixedly connected to the supporting guide rail.

Optionally, the first chain groove includes a first sub groove and a second sub groove, the first sub groove and the second sub groove are symmetrically disposed on the upper and lower sides of the inner fork, the second chain groove includes a third sub groove and a fourth sub groove, the third sub groove and the fourth sub groove are symmetrically disposed on the upper and lower sides of the inner fork, an upper end opening of the first through hole is communicated with the first sub groove, a lower end opening of the first through hole is communicated with the second sub groove, an upper end opening of the second through hole is communicated with the third sub groove, and a lower end opening of the second through hole is communicated with the fourth sub groove.

Optionally, the inner side wall of the top plate of the outer fork is fixedly connected with a first chain seat and a second chain seat, one end of the first chain is fixedly connected to the first chain seat, and one end of the second chain is fixedly connected to the second chain seat.

Optionally, the fork assembly further comprises a first chain tensioner fixedly connected to the left end of the support rail and a second chain tensioner fixedly connected to the right end of the support rail, the other end of the first chain is fixedly connected to the first chain tensioner, and the other end of the second chain is fixedly connected to the second chain tensioner.

Optionally, a second roller and a second nylon sliding block are arranged on the front side and the rear side of the outer fork;

an inwards-concave sliding groove is formed in the side wall of the inner fork, the second roller is in rolling contact with the inside of the sliding groove, and the second nylon sliding block is in sliding contact with the inside of the sliding groove.

Optionally, the fork assembly further comprises a travel switch fixedly attached to the support rail.

Optionally, the fork assembly further comprises cameras fixedly connected to the left and right sides of the support rail.

In another aspect, an embodiment of the present invention provides a forklift including the above fork assembly.

Drawings

FIG. 1 is a first schematic view of a fork assembly (with the forks not extended) provided in accordance with one embodiment of the present invention;

FIG. 2 is a second schematic view of a fork assembly (with the forks not extended) provided in accordance with one embodiment of the present invention;

FIG. 3 is a cross-sectional view taken at A-A in FIG. 2;

FIG. 4 is a third schematic view of a fork assembly (with the forks not extended) provided in accordance with one embodiment of the present invention;

FIG. 5 is a cross-sectional view taken at B-B of FIG. 4;

FIG. 6 is a schematic view of a primary motion stage of the fork assembly provided in accordance with one embodiment of the present invention;

FIG. 7 is a first schematic view of a secondary motion stage of the fork assembly provided in accordance with one embodiment of the present invention;

FIG. 8 is a partial cross-sectional view taken at C-C of FIG. 7;

FIG. 9 is a second schematic view of a secondary motion stage of the fork assembly provided in accordance with one embodiment of the present invention;

FIG. 10 is a schematic view of an inner fork of the fork assembly provided by one embodiment of the present invention;

FIG. 11 is a cross-sectional view taken at D-D of FIG. 10;

FIG. 12 is a first schematic view of an outer fork of the fork assembly provided by one embodiment of the present invention;

FIG. 13 is a second schematic view of the outer fork of the fork assembly provided by one embodiment of the present invention;

FIG. 14 is a first schematic view of the fork assembly with the forks extended to the right as provided by one embodiment of the present invention;

FIG. 15 is a cross-sectional view taken at E-E of FIG. 14;

FIG. 16 is a second schematic view of the fork assembly with the forks extended to the right as provided by one embodiment of the present invention;

FIG. 17 is a cross-sectional view at F-F in FIG. 16;

FIG. 18 is a hydraulic schematic of the conduit system of the fork assembly provided by one embodiment of the present invention.

The reference numerals in the specification are as follows:

1. a fork; 11. a front bracket; 12. a first rack; 13. a third rack; 14. a connecting plate; 15. a vertical plate; 16. compounding rollers; 17. a positive roller;

2. a support rail; 21. a first roller; 22. a first nylon slider;

3. a drive assembly; 31. an oil cylinder; 32. a first-stage moving frame; 321. a primary gear; 33. a secondary moving frame; 331. moving the plate; 332. a second rack; 333. a duplicate gear; 3331. a pinion gear; 3332. a bull gear; 34. a bi-directional balancing valve;

4. a pallet fork; 41. an inner fork; 411. a fourth rack; 412. a T-shaped groove; 413. a first chain groove; 4131. A first sub-groove; 4132. a second sub-groove; 414. a second chain groove; 4141. a third sub-groove; 4142. a fourth sub-groove; 415. a first through hole; 416. a second through hole; 417. a chute; 42. an outer fork; 421. a first chain seat; 422. a second chain seat; 423. a second roller; 424. a second nylon slider; 43. a first sprocket; 44. a first sprocket shaft; 45. a second sprocket; 47. a first chain; 48. a second chain;

5. a first chain tensioner.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

As shown in fig. 1 to 18, the fork assembly provided by the embodiment of the present invention includes a fork carriage 1, a support rail 2, a driving assembly 3 and forks 4, wherein the fork carriage 1 includes a front bracket 11, the support rail 2 is fixedly connected to the front bracket 11 along a left-right direction of the forklift, the forks 4 are slidably connected to the support rail 2, and the driving assembly 3 is configured to drive the forks 4 to slide back and forth along the support rail 2.

According to the fork assembly provided by the embodiment of the invention, the supporting guide rail 2 is fixedly connected to the front bracket 11 along the left and right directions of the forklift, the fork 4 is connected to the supporting guide rail 2 in a sliding manner, the driving assembly 3 drives the fork 4 to slide along the supporting guide rail 2 in a reciprocating manner, and the fork 4 can extend out of the left and right side edges of the front bracket 11 when sliding along the supporting guide rail 2, so that the fork 4 extends into the tray fork holes on the goods shelf to load and unload goods, and the goods on the goods shelf on the left and right sides of a roadway can be loaded and unloaded. The forklift provided with the fork assembly does not need to turn 90 degrees in a roadway, and goods on goods shelves at two sides can be loaded and unloaded in the driving process of the roadway, so that the operation capacity of the forklift in a narrow-passage goods shelf warehouse is improved, and the operation efficiency of the forklift is also improved. In addition, the minimum channel width of the roadway can be greatly reduced, the volume ratio and the storage capacity of the warehouse are improved, the area of the warehouse can be saved, the land can be saved, and the economic benefit and the social benefit are remarkable.

In an embodiment, as shown in fig. 1, 3 and 5 to 9, the driving assembly 3 includes a power device, a first-stage moving frame 32 and a second-stage moving frame 33, the power device is fixedly connected to the front bracket 11, the first-stage moving frame 32 is slidably disposed on the front bracket 11, the power device is configured to drive the first-stage moving frame 32 to reciprocally slide along the left and right directions of the forklift, a first-stage gear 321 is disposed on the first-stage moving frame 32, and the first-stage gear 321 is rotatably connected to the first-stage moving frame 32.

A first rack 12 is fixedly connected to the front bracket 11. The secondary moving frame 33 includes a moving plate 331 and a second rack 332, the second rack 332 is fixed at the bottom of the moving plate 331, the primary gear 321 is simultaneously engaged with the first rack 12 and the second rack 332, and the fork 4 is linked with the moving plate 331.

When the first-stage moving frame 32 slides back and forth in the left and right directions of the forklift under the driving of the power device, the first-stage gear 321 reciprocates in the left and right directions of the forklift along with the first-stage moving frame 32. The primary gear 321 is simultaneously engaged with the first rack 12 and the second rack 332, and the primary gear 321 drives the secondary moving frame 33 to reciprocate along the left and right directions of the forklift. According to the mechanical transmission principle, the moving stroke of the secondary moving frame 33 in the extending and retracting direction (X direction, i.e., the left and right direction of the forklift) is 2 times of the moving stroke of the primary gear 321, i.e., the moving stroke of the secondary moving frame 33 in the extending and retracting direction is 2 times of the moving stroke of the primary moving frame 32, and the forks 4 are linked with the moving plate 331 of the secondary moving frame 33, so that the moving stroke of the forks 4 is increased in multiples.

In one embodiment, as shown in fig. 5, a third rack 13 is further fixedly connected to the front bracket 11, and a fourth rack 411 is provided on a side wall of the fork 4. The secondary moving frame 33 further includes a duplicate gear 333, the duplicate gear 333 includes a pinion gear 3331 and a bull gear 3332 which are coaxially connected, the pinion gear 3331 is engaged with the third rack 13, and the bull gear 3332 is engaged with the fourth tooth 411.

In the double gear 333, the small gear 3331 and the large gear 3332 rotate synchronously, and the diameter of the small gear 3331 is smaller than that of the large gear 3332.

When the secondary moving frame 33 reciprocates along the left and right directions of the forklift under the driving action of the primary gear 321, the pinion 3331 is engaged with the third rack 13, and the large gear 3332 is engaged with the fourth rack 411 to push the pallet fork 4 to reciprocate along the left and right directions of the forklift. Since the diameter of the small gear 3331 is smaller than that of the large gear 3332, the moving stroke of the forks 4 in the telescopic direction (X direction, i.e., the left and right direction of the forklift) is larger than that of the secondary moving frame 33 according to the mechanical transmission principle, so that the moving stroke of the forks 4 is further increased.

In one embodiment, as shown in fig. 5 and 17, the second rack 332 is located above the first rack 12, and the stage gear 321 is located between the second rack 332 and the first rack 12, so that the stage gear 321 can be meshed with the first rack 12 and the second rack 332 simultaneously. The fourth rack 411 is located above the third rack 13, the third rack 13 is located above the second rack 332, and the dual gear 333 is located between the third rack 13 and the second rack 332, so that the dual gear 333 can be engaged with the third rack 13 and the second rack 332 at the same time, that is, the pinion 3331 is engaged with the third rack 13, and the bull gear 3332 is engaged with the fourth rack 411, so as to drive the fork 4.

In an embodiment not shown in the figures, the second rack may also be located below the first rack, the fourth rack may also be located below the third rack, and the third rack may also be located below the second rack. Only by ensuring that the first-stage gear is positioned between the second rack and the first rack, and the duplicate gear is positioned between the third rack and the second rack.

In one embodiment, as shown in fig. 3, the power device uses an oil cylinder 31 powered by a hydraulic oil source, a piston rod of the oil cylinder 31 is parallel to the support rail 2, and the primary moving frame 32 is fixedly connected to the piston rod of the oil cylinder 31.

Specifically, the oil cylinder 31 is a two-way through piston rod, and two ends of the two-way through piston rod respectively penetrate through the left side and the right side of the cylinder body of the oil cylinder 31 and are fixedly connected with the first-stage moving frame 32. As shown in fig. 16, when the bidirectional through piston rod moves to one side, the primary moving frame 32 moves together with the bidirectional through piston rod to move the primary gear 321.

In order to prevent the situation where the forks 4 move along with the oil pipe passing through the pulleys of the forklift mast due to wear breakage or cylinder leakage, and the movement of the cylinder 31 due to the inertia of the forks 4 or the load, as shown in fig. 18, a two-way balance valve 34 is provided in a piping system connecting the cylinder 31 and the oil pump. Only under the condition that the oil inlet pipe has pressure, the oil return pipe can be opened for oil return, so that the oil cylinder 31 cannot move randomly, and the condition that the pallet fork 4 automatically slides when a pipeline is broken or the oil cylinder leaks is avoided.

In an embodiment not shown in the drawings, the piston rod of the oil cylinder may also extend from only one end of the cylinder body of the oil cylinder, and it is only necessary to ensure that the primary moving frame 32 can be fixedly connected with the piston rod.

In the embodiment not shown in the figure, the power device can also adopt other power driving devices such as a hydraulic motor, a pneumatic push rod, a motor and a speed reducer or an electric push rod.

In one embodiment, as shown in fig. 1, 4, 5 and 10 to 13, the fork 4 includes an inner fork 41 and an outer fork 42 slidably connected to an outer side of the inner fork 41, and the inner fork 41 is slidably connected to the support rail 2.

The fork 4 adopts a two-stage extending structure consisting of the inner fork 41 and the outer fork 42, so that the extending distance of the side surface of the fork 4 is longer, and the fork is convenient to fork goods.

In one embodiment, as shown in fig. 4 and 14, the front and rear sides of the support rail 2 are provided with a first roller 21 and a first nylon slider 22. The inner fork 41 is formed with a T-shaped groove 412 with an open lower end, and the first roller 21 is in rolling contact with the T-shaped groove 412 to slidably connect the inner fork 41 to the support rail 2. The first nylon slider 22 is in sliding contact with the T-shaped groove 412 to limit the left and right gaps between the inner fork 41 and the support rail 2, and to ensure that the inner fork 41 is not deflected.

Preferably, a grease cup is installed on the roller shaft of the first roller 21, so as to lubricate the first roller 21, ensure the reliability of the mechanism, and prolong the life of the first roller 21.

In an embodiment, as shown in fig. 10 and 11, the inner fork 41 is provided with a first chain groove 413 and a second chain groove 414 which are arranged along the left-right direction of the forklift, a left end of the first chain groove 413 is provided with a first through hole 415, and a right end of the second chain groove 414 is provided with a second through hole 416.

As shown in fig. 10, 12 and 16, the fork 4 further includes a first sprocket 43, a first sprocket shaft 44, a second sprocket 45, a second sprocket shaft (not shown), a first chain 47 and a second chain 48, the first sprocket shaft 44 is fixed in the first through hole 415 along the front-rear direction of the forklift, the first chain 43 is rotatably connected to the first sprocket shaft 44, the second sprocket shaft is fixed in the second through hole 416 along the front-rear direction of the forklift, the second sprocket 45 is rotatably connected to the second sprocket shaft, the first chain 47 is wound around the first sprocket 43, one end of the first chain 47 is fixedly connected to the inner sidewall of the top plate of the outer fork 42, the other end of the first chain 47 is fixedly connected to the support rail 2, the second chain 48 is wound around the second sprocket 45, one end of the second chain 48 is fixedly connected to the inner side wall of the top plate of the outer fork 42, and the other end of the second chain 48 is fixedly connected to the support rail 2.

When the secondary moving frame 33 moves rightwards, one end of the first chain 47 is fixedly connected to the inner side wall of the top plate of the outer fork 42, the other end of the first chain 47 is fixedly connected to the supporting rail 2, since the forks 4 are moved rightward by the secondary moving frame 33, the length of the side of the first chain 47 fixedly connected to the support rail 2 (the side of the first chain 47 fixedly connected to the support rail 2 is the bottom side when the forks 4 are placed in the direction shown in fig. 14 and 15) is increased, and the length of the side of the first chain 47 fixedly connected to the top plate of the outer fork 42 (the side of the first chain 47 fixedly connected to the top plate of the outer fork 42 is the top side when the forks 4 are placed in the direction shown in fig. 14 and 15) is decreased, so that the outer fork 42 is moved rightward.

When the secondary moving frame 33 moves leftward, one end of the second chain 48 is fixedly connected to the inner sidewall of the top plate of the outer fork 42, the other end of the second chain 48 is fixedly connected to the supporting rail 2, since the forks 4 are moved leftward by the secondary moving frame 33, the length of the side of the second chain 48 fixedly connected to the support rail 2 (when the forks 4 are placed in the direction shown in fig. 14 and 15, the side of the second chain 48 fixedly connected to the support rail 2 is the bottom side) is increased, and the length of the side of the second chain 48 fixedly connected to the top plates of the outer forks 42 (when the forks 4 are placed in the direction shown in fig. 14 and 15, the side of the first chain 47 fixedly connected to the top plates of the outer forks 42 is the top side) is decreased, so that the outer forks 42 are moved leftward.

In an embodiment, as shown in fig. 10 and 11, the first chain groove 413 includes a first sub groove 4131 and a second sub groove 4132, the first sub groove 4131 and the second sub groove 4132 are symmetrically disposed on the upper and lower sides of the inner fork 41, an upper end opening of the first through hole 415 is communicated with the first sub groove 4131, and a lower end opening of the first through hole 415 is communicated with the second sub groove 4132, so that both ends of the first chain 47 wound around the first sprocket 43 and passing through the first through hole 415 are respectively located in the first sub groove 4131 and the second sub groove 4132, and the first chain 47 is always located in the first chain groove 413.

The second chain groove 414 includes a third minute groove 4141 and a fourth minute groove 4142, the third minute groove 4141 and the fourth minute groove 4142 are symmetrically disposed at upper and lower sides of the inner fork 41, an upper end opening of the second through hole 416 is communicated with the third minute groove 4141, a lower end opening of the second through hole 416 is communicated with the fourth minute groove 4142, so that both ends of the second chain 48 wound around the second sprocket 45 and passing through the second through hole 416 are respectively located in the third minute groove 4141 and the fourth minute groove 4142, and the second chain 48 is always located in the second chain groove 414.

In an embodiment, as shown in fig. 12 and 13, a first chain seat 421 and a second chain seat 422 are fixedly connected to an inner side wall of a top plate of the outer fork 42, one end of the first chain 47 is fixedly connected to the first chain seat 421, and one end of the second chain 48 is fixedly connected to the second chain seat 422, so as to fixedly connect one end of the first chain 47 to the inner side wall of the top plate of the outer fork 42 and fixedly connect one end of the second chain 48 to the inner side wall of the top plate of the outer fork 42.

In one embodiment, as shown in fig. 2, the fork assembly further comprises a first chain tensioner 5 and a second chain tensioner (not shown), the first chain tensioner 5 is fixedly connected to the left end of the support rail 2, the second chain tensioner is fixedly connected to the right end of the support rail 2, the other end of the first chain 47 is fixedly connected to the first chain tensioner 5, and the other end of the second chain 48 is fixedly connected to the second chain tensioner, so as to fixedly connect the other end of the first chain 47 to the support rail 2 and fixedly connect the other end of the second chain 48 to the support rail 2.

In one embodiment, as shown in fig. 12 and 13, the outer fork 42 is provided with a second roller 423 and a second nylon sliding block 424 at the front and rear sides thereof. Correspondingly, as shown in fig. 11, an inward recessed slide groove 417 is formed on a side wall of the inner fork 41, and the second roller 423 is in rolling contact with the slide groove 417 to slidably connect the outer fork 42 to the inner fork 41. The second nylon slider 424 is slidably contacted with the slide groove 417 to limit the left and right gaps between the outer fork 42 and the inner fork 41, thereby preventing the outer fork 42 from being deflected.

Preferably, a grease cup is installed on a roller shaft of the second roller 423 to lubricate the second roller 423, thereby ensuring the reliability of the mechanism and extending the life of the second roller 423.

In one embodiment, in order to prevent the fork truck from pushing or pulling the pallet when the fork 4 is extended, which may be caused by careless or faulty operation of the truck by the driver, the fork assembly further comprises a travel switch (not shown) fixedly connected to the support rail 2. Specifically, the travel switches may be provided on both left and right sides of the support rail 2, respectively.

When the fork 4 extends leftwards or rightwards, the travel switch cuts off a walking control circuit of the forklift through a control circuit, so that the forklift cannot walk. Only when the fork 4 returns to the neutral position can the fork move forward or backward.

In one embodiment, the fork assembly further comprises cameras (not shown) fixedly attached to the left and right sides of the support rail 2. Through setting up the camera, the driver can follow the position of seeing the pallet fork for the tray jack of goods shelves on fork truck's the display screen, makes the operation more convenient and safe.

Specifically, the cameras may be respectively disposed on the left and right sides of the support rail 2, and the cameras may be wired micro cameras or wireless micro cameras.

In one embodiment, as shown in fig. 1 and 4, the fork 1 further includes a connecting plate 14, two vertical plates 15, a compound roller 16 and a positive roller 17, the front bracket 11 is located in front of the connecting plate 14, the two vertical plates 15 are longitudinally fixed behind the connecting plate 14, and the compound roller 16 and the positive roller 17 are both rotatably connected to the vertical plates 15. Two equal fixedly connected with chain connecting seat on the riser 15 is through the one end fixed connection with a chain on the chain connecting seat to with the other end fixed connection of this chain in the channel-section steel of fork truck's portal, so that fork frame 1 can reciprocate relatively fork truck's portal, realizes the loading and unloading of goods on the different level goods shelves of tunnel both sides dibit.

The embodiment of the invention also provides a forklift which comprises the fork assembly of the embodiment.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.