Integral type side shifting device with buffering structure and forklift

Abstract

The invention relates to the technical field of forklifts, and discloses an integral type lateral moving device with a buffer structure and a forklift, the integral type lateral moving device comprises a supporting assembly, the lateral moving assembly moves in the length direction of the supporting assembly, and the lateral moving assembly comprises a hydraulic oil cylinder internally provided with a left cavity and a right cavity; and the pressure relief assembly forms a channel communicating the left cavity and the right cavity, the channel forms a switch piece for controlling the on-off state, the resultant force of the left cavity and the right cavity to the switch piece changes the on-off state of the switch piece, and the change trend that the oil pressure difference of the left cavity and the right cavity tends to zero is formed. The hydraulic oil cylinder is arranged to drive the pallet fork to move to the limiting position relative to the supporting assembly, the communicating state of the left cavity and the right cavity is controlled by adjusting the length of the left cavity and the right cavity, the oil pressure difference of the left cavity and the right cavity is reduced when the pallet fork moves to the limiting positions on the left side and the right side, and the pallet fork has the deceleration process to avoid hard impact on the supporting assembly; impact on the pallet fork is reduced, and the stability of the pallet fork for carrying goods is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of forklifts, and in particular to an integral side shift device with a buffer structure and a forklift. Background Art

[0002] A forklift sideshifter is connected to the forklift's lifting mechanism and uses hydraulics to achieve lateral movement of the forks, allowing the operator to precisely align the forks with pallets or shelves without adjusting the entire vehicle. This makes it suitable for high-precision applications such as containers and narrow-aisle warehouses. Mainstream sideshifters include split and integrated sideshifters. Integrated sideshifters utilize a hydraulic drive system for lateral movement and require a limiter to prevent them from disengaging from the rails during movement.

[0003] Published Chinese patent CN220317303U discloses a side shifter and forklift. The side shifter comprises a frame, a shift fork mounted on the frame for lateral translation, and two sets of shift forks positioned on either side of the frame's mounting surface. Each shift fork is driven for translation by its own drive assembly, and the shift forks are used to mount the cargo forks. The forks are provided with upper and lower latches protruding toward the edges at their upper and lower ends for securing the cargo forks. The mounting surface of the forks is provided with first and second limit blocks on either side of the cargo fork for left and right positioning. The side shifter achieves lateral shifting of the cargo forks by means of shift forks mounted on the frame for lateral translation, and the first and second limit blocks limit the left and right extreme positions of the shift forks. However, the patent's limiting mechanism uses mechanical hard limits. The shift forks stop moving after colliding with the first limit block, which can cause significant impact on various components, affecting the connection strength between them and generating impact noise. Summary of the Invention

[0004] In order to solve the problems of the mechanical hard limiter in the integrated side shifter generating impact noise and affecting the connection strength between the components, the present invention provides an integrated side shifter with a buffer structure and a forklift. The specific technical solution is as follows:

[0005] An integral side-shifting device with a buffer structure comprises: a support assembly for supporting the movement of a side-shifting assembly, the side-shifting assembly moves along the length direction of the support assembly, the side-shifting assembly comprises a hydraulic cylinder with a left chamber and a right chamber formed therein; and a pressure relief assembly, the pressure relief assembly forms a channel connecting the left chamber and the right chamber, the channel forms a switch member for controlling the on-off state, the combined force of the left chamber and the right chamber on the switch member changes the opening and closing state of the switch member, so as to form a trend in which the oil pressure difference between the left chamber and the right chamber approaches zero.

[0006] Furthermore, the pressure relief assembly also includes a pressure relief hole arranged in the channel. When the pressure relief hole becomes larger, the upper limit of the hydraulic oil flow rate inside the channel becomes larger. When the pressure relief hole becomes smaller, the upper limit of the hydraulic oil flow rate inside the channel becomes smaller. When the pressure relief hole is zero, the hydraulic oil inside the channel stops flowing.

[0007] Preferably, the pressure relief assembly also includes a pressure relief seat and a pressure relief ball arranged in the channel; a cavity for placing the pressure relief ball is formed inside the pressure relief seat, and a through hole is formed through the cavity relative to the side wall of the channel of the pressure relief seat, and the gap between the pressure relief ball and the through hole is the pressure relief hole, and the length change of the left chamber or the right chamber can control the movement state of the pressure relief ball relative to the through hole to control the size of the gap; the maximum diameter of the pressure relief ball is Dmax, and the diameter of the through hole is D1, and Dmax>D1.

[0008] Preferably, the hydraulic cylinder also includes a left plunger rod and a right plunger rod placed inside the left chamber and the right chamber, respectively. The diameters of the left plunger rod and the right plunger rod are respectively the same as the inner diameters of the left chamber and the right chamber, and the left plunger rod and the right plunger rod move along the inner walls of the left chamber and the right chamber, respectively. The change in the distance of the left plunger rod relative to the pressure relief assembly is proportional to the change in the length of the left chamber, and the change in the distance of the right plunger rod relative to the pressure relief assembly is proportional to the change in the length of the right chamber.

[0009] Preferably, the hydraulic cylinder further includes a left ejector pin arranged at one end of the left plunger rod close to the pressure relief assembly, and a right ejector pin arranged at one end of the right plunger rod close to the pressure relief assembly; the diameters of the left ejector pin and the right ejector pin are not larger than the inner diameter of the channel, and when the left plunger rod drives the left ejector pin close to the pressure relief assembly to open the channel, the hydraulic oil inside the left chamber flows into the right chamber through the channel; when the right plunger rod drives the right ejector pin close to the pressure relief assembly to open the channel, the hydraulic oil inside the right chamber flows into the left chamber through the channel, so as to reduce the oil pressure difference between the left chamber and the right chamber to zero.

[0010] Preferably, the channel includes a left channel arranged between the left chamber and the pressure relief assembly, and a right channel arranged between the right chamber and the pressure relief assembly; the pressure relief hole includes a left pressure relief hole for controlling the opening and closing of the left channel and a right pressure relief hole for controlling the opening and closing of the right channel, and the distance between the left pressure relief hole and the right pressure relief hole is M; the length L1 of the left ejector and the length L2 of the left channel satisfy: 0<L1-L2<M, preferably L1-L2=0.5M; the length L3 of the right ejector and the length L4 of the right channel satisfy: 0<L3-L4<M, preferably L3-L4=0.5M.

[0011] Preferably, the hydraulic cylinder also includes a cylinder body with a left chamber and a right chamber formed therein, and a reversing valve respectively connected to the left chamber and the right chamber. The hydraulic oil in the oil tank enters the left chamber or the right chamber through the reversing valve to increase the length of the left chamber or the right chamber.

[0012] Preferably, the side-shift assembly further comprises a side-shift fork frame that moves along the length direction of the support assembly; when hydraulic oil flows into the left chamber and hydraulic oil flows out of the right chamber, the right pressure relief hole is closed, the difference between the oil pressure in the left chamber and the oil pressure in the right chamber gradually increases, the side-shift fork frame moves to the left, and the right ejector moves toward the right pressure relief hole until the right pressure relief hole is opened to connect the left chamber and the right chamber; when hydraulic oil flows into the right chamber and hydraulic oil flows out of the left chamber, the left pressure relief hole is closed, the difference between the oil pressure in the right chamber and the oil pressure in the left chamber gradually increases, the side-shift fork frame moves to the right, and the left ejector moves toward the left pressure relief hole until the left pressure relief hole is opened to connect the left chamber and the right chamber.

[0013] Preferably, the side shift fork frame includes an upper crossbeam for hanging the fork and a lower crossbeam for forming a sliding connection with the fork; the support assembly includes a roller frame connected to the lifting mechanism of the forklift and a lower sliding groove for forming a sliding connection with the side shift fork frame.

[0014] A forklift includes an integral side shift device.

[0015] It can be seen from the above technical solution that the present invention has the following beneficial effects:

[0016] The present invention provides a hydraulic cylinder to drive the fork to move left or right relative to the support assembly to the extreme position, and then controls the connection between the left chamber and the right chamber by adjusting the length of the left chamber and the right chamber, thereby reducing the oil pressure difference between the left chamber and the right chamber when the fork moves to the left and right extreme positions, thereby causing the fork to decelerate, so as to avoid a hard impact with the support assembly, reduce the impact on the fork, and improve the stability of the fork in transporting goods. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic structural diagram of a partial cross section of an embodiment of the present invention;

[0018] Figure 2 for Figure 1 A magnified view of the structure at point B in FIG;

[0019] Figure 3 A schematic structural diagram of a partial cross-section of an embodiment of the present invention;

[0020] Figure 4 for Figure 3 A magnified view of the structure at point C in FIG;

[0021] Figure 5 A schematic diagram of a second structural state of forming a partial cross section of an embodiment of the present invention;

[0022] Figure 6 for Figure 5 A magnified view of the structure at D in FIG;

[0023] Figure 7A schematic diagram of a state where a partial cross section is formed in the embodiment of the present invention;

[0024] Figure 8 for Figure 7 A magnified view of the structure at E in FIG;

[0025] Figure 9 A schematic diagram of a fourth structure of a partial cross section of an embodiment of the present invention;

[0026] Figure 10 for Figure 9 A magnified view of the structure at F in FIG.

[0027] Figure 11 for Figure 1 AA section view in;

[0028] Figure 12 for Figure 11 A magnified view of the structure at G in FIG;

[0029] Figure 13 Schematic diagram of the structure of the fork;

[0030] Figure 14 for Figure 2 A magnified view of the structure at position J in FIG.

[0031] In the figure: 1. Support assembly; 12. Roller frame; 13. Lower slide chute; 2. Side shift assembly; 21. Side shift fork frame; 211. Upper crossbeam; 212. Lower crossbeam; 22. Hydraulic cylinder; 221. Left chamber; 222. Right chamber; 223. Cylinder body; 224. Left plunger rod; 225. Right plunger rod; 226. Left ejector pin; 227. Right ejector pin; 228. Reversing valve; 3. Pressure relief assembly; 31. Left channel; 32. Right channel; 33. Pressure relief seat; 34. Left pressure relief hole; 35. Right pressure relief hole; 36. Pressure relief ball; 4. Fork; 41. Upper bracket; 42. Lower bracket. DETAILED DESCRIPTION

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0033] In the description of the embodiments of the present invention, it should be noted that the terms "inside", "outside", "upper", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0034] Example 1

[0035] like Figure 1 and Figure 2 As shown, this embodiment 1 is an integral side-shifting device with a buffer structure, comprising: a support assembly 1 for supporting the movement of the side-shifting assembly 2, the side-shifting assembly 2 moves along the length direction of the support assembly 1, the side-shifting assembly 2 includes a hydraulic cylinder 22 with a left chamber 221 and a right chamber 222 formed therein; and a pressure relief assembly 3, the pressure relief assembly 3 forms a channel connecting the left chamber 221 and the right chamber 222, the channel forms a switch component for controlling the on-off state, and the combined force of the left chamber 221 and the right chamber 222 on the switch component changes the opening and closing state of the switch component, so as to form a trend in which the oil pressure difference between the left chamber 221 and the right chamber 222 tends to zero.

[0036] Specifically, the length direction of the support assembly 1 is defined as the left and right direction of the side shift assembly 2 and the pressure relief assembly 3. Secondly, in the field of forklifts, the forklift includes a lifting mechanism (not shown in the figure) for lifting and lowering, the support assembly 1 is connected to the lifting mechanism, and the side shift assembly 2 moves left and right along the length direction of the support assembly 1. It is relatively fixed with the left fork 4 and the right fork 4 (the connection structure of the paired forks 4 and the side shift assembly 2 is not shown in the figure, which is a common structure in this field), and then the side shift assembly 2 can drive the left fork 4 and the right fork 4 to move left and right; secondly, the hydraulic cylinder 22 includes a cylinder body 223 and a telescopic rod, the cylinder body 223 is fixedly connected to the support assembly 1, and the telescopic rod drives the fork 4 to move left and right with the cylinder body 223 as the reference, wherein the hydraulic cylinder 22 is a double-cylinder cylinder, a left chamber 221 is formed inside its left end, and a right chamber 222 is formed inside its right end, and its middle position is fixedly connected to the pressure relief assembly 3. Secondly, in this embodiment, the fork 4 moves to the left at the same time until it reaches the left limit position, which is the limit position where the rightmost side of the support assembly 1 is opposite to the rightmost side shift assembly 2. The fork 4 moves to the right at the same time until it reaches the right limit position, which is the limit position where the leftmost side of the support assembly 1 is opposite to the leftmost side shift assembly 2. The distance between the forks 4 is fixed.

[0037] Secondly, the pressure relief assembly 3 forms a switch component that can control the opening and closing of the channel. There is an oil pressure difference between the left chamber 221 and the right chamber 222, so that the combined force exerted on the switch component is directed to the chamber with low oil pressure, thereby driving the switch component to change the opening and closing state. The oil pressure difference between the left and right chambers 222 can control the opening or closing of the switch component. Among them, when the hydraulic oil continues to flow into the left chamber 221, the fork 4 moves to the left at the same time, and the oil pressure in the left chamber 221 is greater than the oil pressure in the right chamber 222. The length of the left chamber 221 increases, that is, it moves away from the pressure relief component 3, and the length of the right chamber 222 decreases, that is, it approaches the pressure relief component 3. At this time, the switch is closed and the channel is disconnected until the right chamber 222 contacts the pressure relief component 3 to open the switch, and then the left chamber 221 and the right chamber 222 are connected, and the oil pressures of the left chamber 221 and the right chamber 222 tend to be consistent until they are the same. At this time, the side shift assembly 2 drives the fork 4 to move to the left limit position. In the process of the oil pressure tending to be consistent, the speed of the fork 4 gradually decreases until it is zero, so that there is a deceleration process in the process of the fork 4 reaching the left limit position, and then the fork 4 forms a soft limit with the side shift assembly 2 and the support assembly 1 to reduce the impact when reaching the limit position; the hydraulic oil continues to flow into the right chamber When the fork 4 is in the right position, the oil pressure in the right chamber 222 is greater than that in the left chamber 221. The length of the right chamber 222 increases, that is, it moves away from the pressure relief assembly 3, and the length of the left chamber 221 decreases, that is, it approaches the pressure relief assembly 3. At this time, the switch is closed and the channel is disconnected until the left chamber 221 contacts the pressure relief assembly 3 to open the switch, and then the left chamber 221 and the right chamber 222 are connected, and the oil pressures in the right chamber 222 and the left chamber 221 tend to be consistent. At this time, the side shift assembly 2 drives the fork 4 to move to the right limit position. During the process of the oil pressure tending to be consistent, the speed of the fork 4 gradually decreases until it is zero, so that there is a deceleration process when the fork 4 reaches the right limit position. Then the fork 4, the side shift assembly 2, and the support assembly 1 form a soft limit mechanism to reduce the impact when reaching the limit position, thereby reducing the impact on the goods and other structures.

[0038] Combine Figure 14 As shown, the pressure relief assembly 3 also includes a pressure relief hole arranged in the channel. When the pressure relief hole becomes larger, the upper limit of the hydraulic oil flow rate inside the channel becomes larger. When the pressure relief hole becomes smaller, the upper limit of the hydraulic oil flow rate inside the channel becomes smaller. When the pressure relief hole is zero, the hydraulic oil inside the channel stops flowing.

[0039] Specifically, the pressure relief assembly 3 is arranged in the middle of the channel, and forms a pressure relief hole of adjustable size along the flow direction of the hydraulic oil in the channel. During the left and right flow of the hydraulic oil in the left chamber 221 and the right chamber 222, the size of the pressure relief hole is proportional to the maximum flow rate of the hydraulic oil. Specifically, when the pressure relief hole is enlarged, the flow cross-sectional area of the channel increases, and the volume of the hydraulic oil that can flow through per unit time increases. When the oil pressure difference between the left chamber 221 and the right chamber 222 is the largest, the hydraulic oil flows from the high oil pressure chamber to the low oil pressure chamber, and its flow rate reaches the upper limit of the flow rate. When the oil pressure difference between the left chamber 221 and the right chamber 222 gradually decreases, the flow rate of the hydraulic oil gradually decreases, and the speed of the left chamber 221 and the right chamber 222 both tend to zero, so that there is a buffering process when the fork 4 reaches the left and right extreme positions, reducing the impact on the cargo.

[0040] Furthermore, the pressure relief assembly 3 also includes a pressure relief seat 33 and a pressure relief ball 36 arranged in the channel; a cavity for placing the pressure relief ball 36 is formed inside the pressure relief seat 33, and a through hole is formed through the cavity relative to the side wall of the channel of the pressure relief seat 33, and the gap between the pressure relief ball 36 and the through hole is the pressure relief hole, and the length change of the left chamber 221 or the right chamber 222 can control the movement state of the pressure relief ball 36 relative to the through hole to control the size of the gap; the maximum diameter of the pressure relief ball 36 is Dmax, and the diameter of the through hole is D1, Dmax>D1.

[0041] Specifically, the bottom of the pressure relief seat 33 is fixedly connected to the cylinder body 223 in the middle position of the hydraulic cylinder 22, and a cavity with an open end is formed on its top. A through hole is formed at the position where the side wall of the cavity is connected to the channel. The open end of the cavity is fixedly connected to the cylinder body 223 by bolts, and the bolts form a limit for the position of the open end; a freely rotatable pressure relief ball 36 is placed in the cavity of the pressure relief seat 33. The pressure relief ball 36 is preferably made of titanium alloy to reduce the corrosion of the hydraulic oil. The pressure relief ball 36 is inserted from the open end, and the top and bottom of the pressure relief seat 33 are fixedly connected to the channel by bolts, so that the pressure relief ball 36 can only rotate and move freely in the cavity.

[0042] The surface of the pressure relief ball 36 can overlap with the inner side of the through hole to form a seal, and it can overlap and separate with the inner side of the left through hole or the inner side of the right through hole under the push of external force, thereby forming a switch component of the channel. When the oil pressure of the left chamber 221 is greater than the oil pressure of the right chamber 222, the hydraulic oil pushes the pressure relief ball 36 to move toward the right through hole until its surface overlaps with the inner side of the right through hole, so that the channel is disconnected, the left chamber 221 and the right chamber 222 are disconnected, the length of the left chamber 221 gradually increases, and the length of the right chamber 222 gradually decreases until the internal components of the right chamber 222 contact the pressure relief ball 36 and exert a force on it toward the left chamber 221, so that it separates from the inner side of the right through hole, thereby opening the switch component, so that the hydraulic oil in the left chamber 221 gradually flows into the right chamber 222 until the oil pressures of the two are the same. At this time, the fork 4 reaches the left limit position When the oil pressure in the right chamber 222 is greater than the oil pressure in the left chamber 221, the hydraulic oil pushes the pressure relief ball 36 to move toward the left through hole until its surface coincides with the inner side surface of the left through hole, so that the channel is disconnected, the left chamber 221 and the right chamber 222 are disconnected, the length of the right chamber 222 gradually increases, and the length of the left chamber 221 gradually decreases until the internal components of the left chamber 221 contact the pressure relief ball 36 and exert a force on it toward the right chamber 222, separating it from the inner side surface of the left through hole, and then opening the switch member, so that the hydraulic oil in the right chamber 222 gradually flows into the left chamber 221 until the oil pressures of the two are the same, at which time the fork 4 reaches the right limit position.

[0043] Secondly, when Dmax≤D1, the pressure relief ball 36 is separated from the left through hole or the right through hole and the cavity, and the opening and closing state of the opening and closing mechanism cannot be controlled, and thus the length change of the left chamber 221 and the right chamber 222 cannot be achieved to change the on-off state of the channel.

[0044] Furthermore, the hydraulic cylinder 22 also includes a left plunger rod 224 and a right plunger rod 225 respectively placed inside the left chamber 221 and the right chamber 222. The diameters of the left plunger rod 224 and the right plunger rod 225 are respectively the same as the inner diameters of the left chamber 221 and the right chamber 222. The left plunger rod 224 and the right plunger rod 225 move along the inner walls of the left chamber 221 and the right chamber 222 respectively. The change in the distance of the left plunger rod 224 relative to the pressure relief assembly 3 is proportional to the change in the length of the left chamber 221, and the change in the distance of the right plunger rod 225 relative to the pressure relief assembly 3 is proportional to the change in the length of the right chamber 222.

[0045] Specifically, the pressure relief holes include a left pressure relief hole 34 connected to the left chamber 221, and a right pressure relief hole 35 connected to the right chamber 222. Secondly, the left end of the left plunger rod 224 is a telescopic end, which is connected to the left fork 4. Its outer surface coincides with the inner side of the left chamber 221 and moves relative to it along the axial direction, thereby driving the fork 4 to move along the axial direction of the left chamber 221, that is, the length direction of the support assembly 1, and at the same time, the left chamber 221 forms a sealed cavity with variable height. The right end of the left plunger rod 224 is close to the left pressure relief hole 34. When hydraulic oil enters the left chamber 221, the hydraulic oil pushes the left plunger rod 224 to move to the left, thereby driving the right plunger rod 225 to move to the left, thereby driving the fork 4 moves left as a whole; the right end of the right plunger rod 225 is a telescopic end, which is connected to the right fork 4. The outer surface of the telescopic end coincides with the inner surface of the right chamber 222 and slides relative to each other along the axial direction, thereby driving the right fork 4 to move along the axial direction of the right chamber 222, and at the same time forming a sealed cavity with variable height in the right chamber 222. The left end of the right plunger rod 225 is close to the right pressure relief hole 35. When hydraulic oil enters the right chamber 222, the hydraulic oil pushes the right plunger rod 225 to move rightward, thereby driving the left plunger rod 224 to move rightward, and then driving the fork 4 to move rightward as a whole.

[0046] like Figures 3 to 10 As shown, Figure 3 A schematic diagram showing the state in which the right ejector pin 227 moves to the left and just contacts the pressure relief ball 36. Figure 5 The diagram shows the structure of the second state when the right plunger rod 225 moves to the leftmost position. At this time, the fork 4 as a whole reaches the left limit position. Figure 7 The third structural diagram shows the state where the left ejector pin 226 moves to the right and just contacts the pressure relief ball 36. Figure 9 FIG4 is a structural diagram showing a state in which the left plunger rod 224 moves to the rightmost position, at which time the fork 4 as a whole reaches the right limit position.

[0047] Furthermore, the hydraulic cylinder 22 also includes a left ejector pin 226 arranged at one end of the left plunger rod 224 close to the pressure relief assembly 3, and a right ejector pin 227 arranged at one end of the right plunger rod 225 close to the pressure relief assembly 3; the diameters of the left ejector pin 226 and the right ejector pin 227 are not larger than the inner diameter of the channel. When the left plunger rod 224 drives the left ejector pin 226 close to the pressure relief assembly 3 to open the channel, the internal hydraulic oil of the left chamber 221 flows into the right chamber 222 through the channel. When the right plunger rod 225 drives the right ejector pin 227 close to the pressure relief assembly 3 to open the channel, the internal hydraulic oil of the right chamber 222 flows into the left chamber 221 through the channel to reduce the oil pressure difference between the left chamber 221 and the right chamber 222 to zero.

[0048] Specifically, the left end of the left ejector pin 226 is fixedly connected to the right end of the left plunger rod 224, and is coaxial with the left plunger rod 224. The diameter of its right end is smaller than the diameter of the channel and the through hole of the pressure relief seat 33. The top end of the ejector pin 226 can pass through the through hole and apply a pushing force to the right along the axial direction to the pressure relief ball 36; the right end of the right ejector pin 227 is fixedly connected to the left end of the right plunger rod 225, and is coaxial with the right plunger rod 225. The diameter of its right end is smaller than the diameter of the channel and the through hole of the pressure relief seat 33. The top end of the ejector pin 227 can pass through the through hole and apply a pushing force to the left along the axial direction to the pressure relief ball 36.

[0049] like Figure 3 、 Figure 4 、 Figure 5 and Figure 6 As shown, the oil pressure in the left chamber 221 is greater than the oil pressure in the right chamber 222. The hydraulic oil in the left chamber 221 applies rightward pressure to the pressure relief ball 36. The pressure relief ball 36 moves to the right through-hole to close the switch. The size of the right pressure relief hole 35 is zero. The left chamber 221 continues to inject hydraulic oil, and its length increases. The length of the right chamber 222 decreases. The left end of the right ejector pin 227 begins to apply thrust to the pressure relief ball 36 to resist the pressure applied by the high-pressure hydraulic oil in the left chamber 221. The size of the right pressure relief hole 35 gradually increases, and the channel gradually opens. The high-pressure hydraulic oil in chamber 221 enters the right chamber 222 through the channel and the right pressure relief hole 35, so that the oil pressure between the two tends to be consistent, causing the speed of the fork 4 moving to the right to gradually decrease until the right plunger rod 225 moves to the leftmost position of the right chamber 222, and the impact on the fork 4 and the cargo is minimized; among them, when the right plunger rod 225 drives the right ejector 227 to move to the leftmost position, the sizes of the left pressure relief hole 34 and the right pressure relief hole 35 are not zero, the switch is always open, and the left chamber 221 and the right chamber 222 are always connected.

[0050] Secondly, if Figure 7 、 Figure 8 、 Figure 9 and Figure 10As shown, the oil pressure of the right chamber 222 is greater than the oil pressure of the left chamber 221. The hydraulic oil in the right chamber 222 applies leftward pressure to the pressure relief ball 36. The pressure relief ball 36 moves to the left through-hole to close the opening and closing mechanism. The size of the left pressure relief hole 34 is zero. The right chamber 222 continues to inject hydraulic oil, and its length gradually increases, thereby driving the left chamber 221 to gradually move to the right, and its length gradually decreases. The right end of the left ejector pin 226 begins to apply thrust to the pressure relief ball 36 to resist the pressure applied by the high-pressure hydraulic oil in the right chamber 222. The left pressure relief hole 34 is zero. As the size of 34 gradually increases and the channel gradually opens, the high-pressure hydraulic oil in the right chamber 222 enters the left chamber 221 through the channel and the left pressure relief hole 34, so that the oil pressure between the two tends to be consistent until the oil pressure difference is equal to zero. The fork 4 and the cargo are located at the right extreme position, and the impact on both is minimized. Among them, when the left plunger rod 224 drives the left ejector pin 226 to move to the rightmost position, the sizes of the left pressure relief hole 34 and the right pressure relief hole 35 are not zero, the switch is always open, and the left chamber 221 and the right chamber 222 are always connected.

[0051] Furthermore, the channel includes a left channel 31 arranged between the left chamber 221 and the pressure relief assembly 3, and a right channel 32 arranged between the right chamber 222 and the pressure relief assembly 3; the pressure relief hole includes a left pressure relief hole 34 for controlling the opening and closing of the left channel 31 and a right pressure relief hole 35 for controlling the opening and closing of the right channel 32, and the distance between the left pressure relief hole 34 and the right pressure relief hole 35 is M; the length L1 of the left ejector 226 and the length L2 of the left channel 31 satisfy: 0<L1-L2<M, preferably L1-L2=0.5M; the length L3 of the right ejector 227 and the length L4 of the right channel 32 satisfy: 0<L3-L4<M, preferably L3-L4=0.5M.

[0052] like Figure 4 As shown, the left end of the right ejector 227 just contacts the pressure relief ball 36. The dotted pressure relief ball 36 in the figure represents the pressure relief ball 36 at the leftmost position. The distance between the center of the pressure relief ball 36 at the leftmost position and the center of the pressure relief ball 36 at the rightmost position is a distance M. The distance between the left end of the right ejector 227 and the left side wall of the right chamber 222 in the figure is the length L4 of the right channel 32. The distance between the left end of the right ejector 227 and the left end of the right plunger rod 225 is the length L3 of the right ejector 227. When L3-L4≥M When the right ejector pin 227 moves to the leftmost position, the surface of the pressure relief ball 36 coincides with the inner surface of the left through hole, the size of the left pressure relief hole 34 is zero, and the left channel 31 and the right channel 32 are closed, which does not meet the requirements. In the preferred embodiment, L3-L4=0.5M, so that when the right ejector pin 227 moves to the leftmost position, the pressure relief ball 36 is located in the middle position of the cavity, ensuring that the sizes of the left pressure relief hole 34 and the right pressure relief hole 35 are the same, thereby increasing the maximum flow rate in the channel and reducing the buffering time of the fork 4.

[0053] like Figure 8As shown, the right end of the left ejector 226 just contacts the pressure relief ball 36. The dotted pressure relief ball 36 in the figure represents the pressure relief ball 36 at the rightmost position. The distance between the center of the pressure relief ball 36 at the leftmost position and the center of the pressure relief ball 36 at the rightmost position is a distance M. The distance between the right end of the left ejector 226 and the right side wall of the left chamber 221 in the figure is the length L2 of the left channel 31. The distance between the right end of the left ejector 226 and the right end of the left plunger rod 224 is the length L1 of the left ejector 226. When L1-L2≥M , the left ejector 226 moves to the rightmost position, the surface of the pressure relief ball 36 coincides with the inner surface of the right through-hole, the size of the right pressure relief hole 35 is zero, the left channel 31 and the right channel 32 are closed, which does not meet the production requirements. In the preferred embodiment, L1-L2=0.5M, so that when the left ejector 226 moves to the rightmost position, the pressure relief ball 36 is located in the middle position of the cavity, ensuring that the left pressure relief hole 34 and the right pressure relief hole 35 have the same size, thereby increasing the maximum flow rate in the channel and reducing the buffering time of the fork 4.

[0054] like Figure 2 As shown, the hydraulic cylinder 22 also includes a cylinder body 223 that forms a left chamber 221 and a right chamber 222 therein, and a reversing valve 228 that is respectively connected to the left chamber 221 and the right chamber 222. The hydraulic oil in the oil tank enters the left chamber 221 or the right chamber 222 through the reversing valve 228 to increase the length of the left chamber 221 or the right chamber 222.

[0055] Specifically, the left end of the cylinder body 223 forms a left chamber 221, and the right end thereof forms a right chamber 222, and the two are integrated; the left reversing valve 228 is connected to the left channel 31, and the right reversing valve 228 is connected to the right channel 32, and the reversing valve 228 can control the flow rate and flow direction of the hydraulic oil; when the hydraulic oil enters the left chamber 221 through the reversing valve 228, the length of the left chamber 221 increases, and the fork 4 moves to the left. In order to achieve the simultaneous movement of the fork 4 to the left, thereby driving the cargo to move to the left, the hydraulic oil in the right chamber 222 flows out through the reversing valve 228, and the length of the right chamber 222 decreases; when the hydraulic oil enters the right chamber 222 through the reversing valve 228, the length of the right chamber 222 increases, and the fork 4 moves to the right. In order to achieve the simultaneous movement of the fork 4 to the right, thereby moving the cargo to the right, the hydraulic oil in the left chamber 221 flows out through the reversing valve 228, and the length of the left chamber 221 decreases.

[0056] Furthermore, the side-shift assembly 2 also includes a side-shift fork frame 21 that moves along the length direction of the support assembly 1; when hydraulic oil flows into the left chamber 221 and hydraulic oil flows out of the right chamber 222, the right pressure relief hole 35 is closed, and the difference between the oil pressure of the left chamber 221 and the oil pressure of the right chamber 222 gradually increases, the side-shift fork frame 21 moves to the left, and the right ejector pin 227 moves toward the right pressure relief hole 35 until the right pressure relief hole 35 is opened to connect the left chamber 221 and the right chamber 222; when hydraulic oil flows into the right chamber 222 and hydraulic oil flows out of the left chamber 221, the left pressure relief hole 34 is closed, and the difference between the oil pressure of the right chamber 222 and the oil pressure of the left chamber 221 gradually increases, the side-shift fork frame 21 moves to the right, and the left ejector pin 226 moves toward the left pressure relief hole 34 until the left pressure relief hole 34 is opened to connect the left chamber 221 and the right chamber 222.

[0057] Specifically, the side shift fork frame 21 moves along the length direction of the support assembly 1 through the slide rail, the cylinder body 223 of the hydraulic cylinder 22 is fixedly connected to the support assembly 1, and its bidirectional telescopic ends are respectively connected to the left and right ends of the side shift fork frame 21, so that when the length of the left chamber 221 and the right chamber 222 changes, the side shift fork frame 21 can be driven to move relative to the support assembly 1.

[0058] Among them, hydraulic oil flows into the left chamber 221 through the reversing valve 228, and its length increases to the left, and hydraulic oil flows out of the right chamber 222 through the reversing valve 228, and its length decreases to the left, so that the side shift fork frame 21 moves to the left relative to the support assembly 1, thereby driving the fork 4 as a whole and the cargo to move to the left, until the right ejector pin 227 opens the right pressure relief hole 35 against the high pressure of the left hydraulic oil, so that the left chamber 221 and the right chamber 222 are connected, and the hydraulic oil in the left chamber 221 enters the right chamber 222 through the channel under the action of the pressure difference, thereby making the oil pressure of the left chamber 221 and the right chamber 222 the same, and then when the side shift fork frame 21 is about to reach the left limit position, the speed gradually decreases, thereby avoiding a hard collision between the two when the side shift fork frame 21 reaches the left limit position, causing impact on the cargo and component structure.

[0059] Secondly, hydraulic oil flows into the right chamber 222 through the reversing valve 228, and its length increases to the right, and hydraulic oil flows out of the left chamber 221 through the reversing valve 228, and its length decreases to the right, so that the side shift fork frame 21 moves to the right as a whole relative to the support assembly 1, thereby driving the fork 4 and the cargo to move to the right as a whole, until the left ejector pin 226 opens the left pressure relief hole 34 against the high pressure of the hydraulic oil on the right side, so that the left chamber 221 and the right chamber 222 are connected, and the hydraulic oil in the right chamber 222 enters the left chamber 221 through the channel under the action of the pressure difference, so that the oil pressure of the left chamber 221 and the right chamber 222 are the same, so that when the side shift fork frame 21 is about to reach the right limit position, the speed gradually decreases, thereby avoiding a hard collision between the two when the side shift fork frame 21 reaches the right limit position, causing impact damage to the cargo and component structure.

[0060] like Figure 11 、 Figure 12 and Figure 13 As shown, the side shift fork frame 21 includes an upper crossbeam 211 for hanging the fork 4 and a lower crossbeam 212 for forming a sliding connection with the fork 4; the support assembly 1 includes a roller frame 12 connected to the lifting mechanism of the forklift and a lower sliding groove 13 for forming a sliding connection with the side shift fork frame 21.

[0061] Specifically, the fork 4 is an L-shaped plate, which includes a horizontal plate and a vertical plate. The horizontal plate is used to carry goods, and the vertical plates are welded with an upper bracket 41 and a lower bracket 42 from top to bottom. The upper bracket 41 is connected to the upper crossbeam 211, and the upper crossbeam 211 forms a groove or positioning hole. The upper bracket 41 has a built-in spring positioning pin. When adjusting, the positioning pin is lifted and the fork 4 can slide horizontally. After loosening, the pin is locked into the groove and fixed; secondly, the lower bracket 42 forms a sliding connection with the lower crossbeam 212. The lower crossbeam 212 is a slide rail, and the lower bracket 42 is a slide groove. The lower crossbeam 212 limits the lower bracket 42 to avoid shaking in the length direction of the vertical support assembly 1, thereby improving the stability of the fork 4 during transportation.

[0062] Secondly, the length direction of the roller frame 12 is perpendicular to the length direction of the side shift fork frame 21, and the roller frame 12 is connected to the door frame mechanism of the forklift. The door frame mechanism drives the roller frame 12 to perform lifting and lowering movements through sprocket transmission and guide rail transmission, thereby driving the side shift fork frame 21 and the fork 4 to perform lifting and lowering movements; secondly, the length direction of the lower slide chute 13 is consistent with the length direction of the lower crossbeam 212, and a protrusion is formed on the top of the lower crossbeam 212 as a slide rail matching the lower slide chute 13, so that when the hydraulic cylinder 22 drives the side shift fork frame 21 to move relative to the support assembly 1, the cylinder body 223 of the hydraulic cylinder 22 slides relative to the side shift fork frame 21, and the lower crossbeam 212 of the side shift fork frame 21 slides relative to the lower slide chute 13, thereby improving the stability of the lateral movement of the side shift fork frame 21.

[0063] Example 2

[0064] A forklift includes the integrated side shift device of the first embodiment. The forklift includes a lifting mechanism for lifting the support assembly 1. The lifting mechanism includes a sprocket drive for lifting the support assembly 1 and a guide rail for guiding the support assembly 1.

[0065] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

[0066] The technology, shape, and structure not described in detail in the present invention are all well-known technologies.

Claims

1. An integral side shifting device with a buffer structure, characterized in that: include: A support assembly (1) for supporting the movement of a side shift assembly (2), wherein the side shift assembly (2) moves along the length direction of the support assembly (1), and the side shift assembly (2) includes a hydraulic cylinder (22) forming a left chamber (221) and a right chamber (222) therein; and A pressure relief assembly (3) is provided, wherein the pressure relief assembly (3) forms a channel connecting the left chamber (221) and the right chamber (222), the channel forming a switch element for controlling an on / off state, and the combined force of the left chamber (221) and the right chamber (222) on the switch element changes the on / off state of the switch element, thereby forming a trend in which the oil pressure difference between the left chamber (221) and the right chamber (222) tends to zero.

2. The integrated side shifting device according to claim 1, characterized in that: The pressure relief component (3) further comprises a pressure relief hole arranged in the channel. When the pressure relief hole becomes larger, the upper limit of the hydraulic oil flow rate in the channel becomes larger. When the pressure relief hole becomes smaller, the upper limit of the hydraulic oil flow rate in the channel becomes smaller. When the pressure relief hole is zero, the hydraulic oil in the channel stops flowing.

3. The integrated side shifting device according to claim 2, characterized in that: The pressure relief assembly (3) further includes a pressure relief seat (33) and a pressure relief ball (36) arranged in the channel; The interior of the pressure relief seat (33) forms a cavity for placing the pressure relief ball (36); the pressure relief seat (33) forms a through hole penetrating the cavity relative to the side wall of the channel; the gap between the pressure relief ball (36) and the through hole is the pressure relief hole; the length change of the left chamber (221) or the right chamber (222) can control the movement state of the pressure relief ball (36) relative to the through hole, so as to control the size of the gap; The maximum diameter of the pressure relief ball (36) is Dmax, the diameter of the through hole is D1, and Dmax>D1.

4. The integrated side shifting device according to claim 2, characterized in that: The hydraulic cylinder (22) further comprises a left plunger rod (224) and a right plunger rod (225) respectively placed inside the left chamber (221) and the right chamber (222); the diameters of the left plunger rod (224) and the right plunger rod (225) are respectively the same as the inner diameters of the left chamber (221) and the right chamber (222); the left plunger rod (224) and the right plunger rod (225) respectively move along the inner walls of the left chamber (221) and the right chamber (222); the distance change of the left plunger rod (224) relative to the pressure relief assembly (3) is proportional to the length change of the left chamber (221); the distance change of the right plunger rod (225) relative to the pressure relief assembly (3) is proportional to the length change of the right chamber (222).

5. The integrated side shifting device according to claim 4, characterized in that: The hydraulic cylinder (22) further comprises a left ejector pin (226) arranged at one end of the left plunger rod (224) close to the pressure relief assembly (3), and a right ejector pin (227) arranged at one end of the right plunger rod (225) close to the pressure relief assembly (3); The diameters of the left ejector pin (226) and the right ejector pin (227) are not greater than the inner diameter of the channel. When the left plunger rod (224) drives the left ejector pin (226) close to the pressure relief assembly (3) to open the channel, the hydraulic oil inside the left chamber (221) flows into the right chamber (222) through the channel. When the right plunger rod (225) drives the right ejector pin (227) close to the pressure relief assembly (3) to open the channel, the hydraulic oil inside the right chamber (222) flows into the left chamber (221) through the channel, thereby reducing the oil pressure difference between the left chamber (221) and the right chamber (222) to zero.

6. The integrated side shifting device according to claim 5, characterized in that: The passage comprises a left passage (31) provided between the left chamber (221) and the pressure relief assembly (3), and a right passage (32) provided between the right chamber (222) and the pressure relief assembly (3); The pressure relief holes include a left pressure relief hole (34) for controlling the opening and closing of the left channel (31) and a right pressure relief hole (35) for controlling the opening and closing of the right channel (32), and a distance M between the left pressure relief hole (34) and the right pressure relief hole (35); The length L1 of the left ejector pin (226) and the length L2 of the left channel (31) satisfy: 0<L1-L2<M, preferably L1-L2=0.5M; The length L3 of the right ejector pin (227) and the length L4 of the right channel (32) satisfy the relationship: 0<L3-L4<M, preferably L3-L4=0.5M.

7. The integrated side shifting device according to claim 1, characterized in that: The hydraulic cylinder (22) further comprises a cylinder body (223) in which the left chamber (221) and the right chamber (222) are formed, and a reversing valve (228) respectively connected to the left chamber (221) and the right chamber (222). The hydraulic oil in the oil tank enters the left chamber (221) or the right chamber (222) through the reversing valve (228) to increase the length of the left chamber (221) or the right chamber (222).

8. The integrated side shifting device according to claim 6, characterized in that: The side shift assembly (2) further comprises a side shift fork frame (21) that moves along the length direction of the support assembly (1); When hydraulic oil flows into the left chamber (221) and hydraulic oil flows out of the right chamber (222), the right pressure relief hole (35) is closed, the difference between the oil pressure of the left chamber (221) and the oil pressure of the right chamber (222) gradually increases, the side shift fork frame (21) moves to the left, and the right ejector pin (227) moves toward the right pressure relief hole (35) until the right pressure relief hole (35) is opened, thereby connecting the left chamber (221) and the right chamber (222); When hydraulic oil flows into the right chamber (222) and hydraulic oil flows out of the left chamber (221), the left pressure relief hole (34) is closed, and the difference between the oil pressure of the right chamber (222) and the oil pressure of the left chamber (221) gradually increases. The side shift fork frame (21) moves to the right, and the left ejector pin (226) moves toward the left pressure relief hole (34) until the left pressure relief hole (34) is opened, thereby connecting the left chamber (221) and the right chamber (222).

9. The integrated side shifting device according to claim 8, characterized in that: The side shift fork frame (21) comprises an upper crossbeam (211) for mounting a cargo fork (4) and a lower crossbeam (212) for forming a sliding connection with the cargo fork (4); The support assembly (1) comprises a roller frame (12) connected to a lifting mechanism of a forklift and a lower sliding groove (13) for forming a sliding connection with the side shift fork frame (21).

10. A forklift, characterized in that: Comprising the integrated side shifting device according to any one of claims 1 to 9.

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