Forklift

Abstract

To prevent an increase in the size of a cargo handling device and an increase in manufacturing costs in a forklift equipped with two pairs of upper and lower forks.SOLUTION: A forklift 1 used for cargo handling operations includes upper and lower forks 2 and 3, and a driving force transmission mechanism C that transmits driving force to drive the upper and lower forks 2 and 3 using a single actuator. Because driving force is transmitted by the driving force transmission mechanism C, the two pairs of upper and lower forks 2 and 3 can be driven by a single actuator. Therefore, compared to a configuration that includes two actuators for raising and lowering the two pairs of upper and lower forks, a cargo handling device H does not become larger and the manufacturing costs do not increase.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a forklift truck equipped with two pairs of forks, one above the other. [Background technology]

[0002] BACKGROUND ART Forklifts used for cargo handling operations at industrial sites and the like are known that are equipped with two pairs of upper and lower forks and two actuators that individually raise and lower the two pairs of upper and lower forks (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 2536077 Summary of the Invention [Problem to be solved by the invention]

[0004] Such conventional forklifts equipped with two pairs of forks, one on top and one on bottom, require two actuators to raise and lower the two pairs of forks, which results in problems such as an increased size of the loading device and higher manufacturing costs.

[0005] The present invention aims to prevent the size of the cargo handling device in a forklift truck equipped with two pairs of upper and lower forks from increasing and to prevent an increase in manufacturing costs. [Means for solving the problem]

[0006] A forklift according to a first aspect of the present invention is a forklift used for loading and unloading operations, and includes upper and lower forks positioned above and below, and a driving force transmission mechanism that transmits driving force to drive the upper and lower forks using a single actuator.

[0007] A forklift according to a second aspect of the present invention is the forklift according to the first aspect, wherein the actuator moves one of the upper fork and the lower fork up and down, and the driving force transmission mechanism moves the other of the upper fork and the lower fork up and down by the biasing force of the one fork that moves up and down due to the driving force of the actuator.

[0008] According to the forklift configurations of the first and second aspects, the driving force is transmitted by the driving force transmission mechanism, so that the two pairs of upper and lower forks can be driven by a single actuator. Therefore, compared to a configuration including two actuators for raising and lowering the two pairs of upper and lower forks, the cargo handling device does not become larger in size and the manufacturing costs do not increase.

[0009] A forklift according to a third aspect of the present invention is the forklift according to the second aspect, wherein the actuator is a linear actuator that expands and contracts parallel to the mast. The one fork moves up and down in a direction toward or away from the other fork so as to apply the biasing force. The other fork moves up and down in the direction opposite to the direction in which the one fork moves up and down by the driving force transmission mechanism.

[0010] According to the configuration of the forklift truck according to the third aspect, a linear actuator is used as the actuator, and the driving force transmission mechanism causes the other fork to move up and down in the direction opposite to the direction in which the one fork moves up and down so as to apply the biasing force. Therefore, the drive mechanism including the actuator and the driving force transmission mechanism can be simplified, which reduces the number of parts and leads to space savings.

[0011] A forklift according to a fourth aspect of the present invention is the forklift according to the third aspect, wherein the driving force transmission mechanism is a seesaw member supported at a longitudinal intermediate portion and having rear and front ends that swing up and down. The linear actuator is a double-acting actuator that moves the upper fork up and down. A pressing member driven by the double-acting actuator and lowered together with the upper fork urges the rear end of the seesaw member downward, together with the weight of the upper fork, causing the lower fork to rise together with the front end of the seesaw member.

[0012] According to the forklift configuration of the fourth aspect, the weight of the upper fork, which is driven downward by the double-acting actuator and is caused by gravity, is also added to the biasing force applied by the pressing member to bias the rear end of the seesaw member downward. Therefore, the capacity of the double-acting actuator can be reduced, thereby reducing manufacturing costs. Furthermore, since the drive force transmission mechanism is the seesaw member, the drive force transmission mechanism can be further simplified and its operation is reliable. Furthermore, by changing the length ratio of the rear arm and the front arm that sandwich the intermediate portion of the seesaw member, the output required for the double-acting actuator and the lifting stroke of the upper fork and the lower fork can be adjusted, thereby increasing design flexibility.

[0013] A forklift according to a fifth aspect of the present invention is the forklift according to the fourth aspect, wherein the double-acting actuator is a double-acting hydraulic cylinder.

[0014] In the configuration of the forklift according to the fifth aspect, the double-acting actuator is a double-acting hydraulic cylinder, so hydraulic force acts on both sides of the piston, allowing the lifting and lowering operations to be controlled hydraulically. The use of hydraulic pressure makes it easy to generate power compared to the size, and provides excellent positioning accuracy and responsiveness.

[0015] A forklift according to a sixth aspect of the present invention is the forklift according to the fourth aspect, wherein the rear arm and the front arm that sandwich the middle part of the seesaw member are longer in length than the front arm.

[0016] In the forklift according to the sixth aspect, the length of the rear arm of the drive force transmission mechanism, which is the seesaw member, is longer than the length of the front arm, so that the biasing force of the pressing member that biases the rear end of the seesaw member downward is increased at the front end of the seesaw member, and therefore the lower fork can be lifted with a smaller biasing force.

[0017] A forklift according to a seventh aspect of the present invention is the forklift according to the fourth or sixth aspect, wherein the rear arm and the front arm sandwiching the intermediate portion of the seesaw member are such that the rear arm tilts upward toward the rear and the front arm tilts upward toward the front when the rear end portion is not biased downward by the pressing member.

[0018] According to the forklift configuration of the seventh aspect, the lowest position of the rear end of the seesaw member is not lower than when the seesaw member is straight, so that the forklift can be applied even when there is a height restriction. Moreover, since there is no need to secure a space to avoid interference with the rear end of the seesaw member, as is the case when the seesaw member is straight, the shape of the lower part of the main body that supports the seesaw member does not become irregular, making it easy to secure the required strength of the lower part of the main body and preventing an increase in manufacturing costs.

[0019] A forklift according to an eighth aspect of the present invention is the forklift according to the fourth or sixth aspect, in which the pressing member and the rear end of the seesaw member are in contact with each other, and the pressing member and the rear end of the seesaw member are spaced apart from each other.

[0020] According to the configuration of the forklift according to the eighth aspect, when the pressing member and the rear end of the seesaw member are spaced apart, the relationship between the upper fork and the lower fork can be arbitrarily switched. Also, by adjusting the distance between the pressing member and the rear end of the seesaw member, it is possible to adjust the downward stroke of the upper fork to start lifting the lower fork, the final lift height of the lower fork, and the like.

[0021] A forklift according to a ninth aspect of the present invention is the forklift according to any one of the first to sixth aspects, further comprising a fork width adjustment mechanism for changing the distance between the left and right forks of the upper fork.

[0022] According to the configuration of the forklift truck according to the ninth aspect, the fork width adjustment mechanism can change the distance between the left and right forks of the upper fork, thereby increasing the size of the transported objects that can be loaded on the upper fork and enabling the transport of various types of transported objects. Furthermore, since the actuator moves the upper fork up and down, even when the lower fork is loaded with transported objects, the fork width adjustment mechanism can widen the distance between the left and right forks of the upper fork, thereby allowing the upper fork to be lowered so as not to interfere with the transported objects on the lower fork.

[0023] The "forklift" in this invention is any forklift equipped with at least two pairs of forks (upper and lower) for loading and unloading, but may be equipped with three or more pairs of forks (upper and lower). The "forklift" in this invention also includes forklifts that do not have a moving device equipped with an actuator (for example, those that are moved by human power). [Effects of the Invention]

[0024] As described above, in the forklift according to the present invention, the driving force is transmitted by the driving force transmission mechanism, so that the two pairs of forks (upper and lower) can be driven by a single actuator. Therefore, compared to a configuration that includes two actuators for raising and lowering the two pairs of forks (upper and lower), the cargo handling device does not become larger in size and the manufacturing costs do not increase. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a perspective view of a forklift truck according to an embodiment of the present invention, seen from above the front right, showing a state in which a tip attachment is attached. [Figure 2] FIG. 2 is a perspective view of the forklift truck viewed from above and rear on the right side, showing a state in which a tip attachment is attached. [Figure 3] FIG. 1 shows the state in which the tip attachment has been removed. [Figure 4] FIG. 2 is a perspective view of the forklift truck as viewed from above the front right, showing a state in which a tip attachment, a cover, etc. have been removed. [Figure 5] 5 is a view of the forklift truck of FIG. 4 as seen from the right. [Figure 6] FIG. 6 is a partially exploded perspective view showing a part of the forklift truck of FIGS. 4 and 5, as viewed from above and rear on the right side. [Figure 7] This is a schematic view seen from the rear, primarily to explain the fork width adjustment mechanism, with covers and the like removed, and the frame for mounting the cylinder tube of the double-acting hydraulic cylinder and the like omitted. [Figure 8] This is an oblique view from the upper right front showing the coffin placed on the upper fork. [Figure 9] This is an oblique view from above the right front showing the operation of placing the coffin on the trivet on the furnace cart using the upper fork. [Figure 10] This is a schematic view from the right showing a forklift truck picking up the in-furnace cart that has left the crematorium. [Figure 11]11 is a schematic view seen from the right, showing the state in which the forklift has moved forward from the state in FIG. 10 and the engagement between the chain conveyor side engagement portion and the furnace cart side engagement portion has been released. FIG. [Figure 12] This is an oblique view from the upper right front showing the state in which an in-furnace cart is placed on the lower fork and bones are collected after cremation. DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following embodiment, as an example of the forklift of the present invention, a forklift equipped with two pairs of upper and lower forks for transporting coffins and furnace carts in a funeral home will be described. However, the forklift of the present invention can also handle various objects other than coffins and furnace carts.

[0027] In the following embodiments, the direction from the base of the forklift's forks to the tip is defined as the front (arrow F in the figure is the front), and the opposite direction is defined as the rear (arrow B in the figure is the rear), and left and right are defined as looking forward (arrow L in the figure is the left, and arrow R in the figure is the right).

[0028] 1 and 2, a forklift 1 according to an embodiment of the present invention has a door 25, a center cover 21, and side covers 22 at its rear, side panels 23 at its left and right sides, and a tip attachment 24 at its front. When the forklift 1 is used for cargo handling, the tip attachment 24 is removed as shown in FIG. 3.

[0029] [Mobile device] As shown in Figures 4 and 5, the forklift 1 is equipped with a transport device T for transporting the forklift. The transport device T consists of a driving wheel O, which is a steering wheel, located in the center of the left-right direction at the rear end of the forklift 1, and left and right driven wheels N located below the upper fork 2 and lower fork 3. The left and right driven wheels N are attached to the center of the left and right legs UL, UR in the fore-and-aft direction, and there is a space S between the left and right legs UL, UR. The operation panel P can be used to switch between forward and reverse travel and travel speed, and steering can be achieved by operating the operating rod Q.

[0030] [Load handling equipment] As shown in Figures 4 to 6, the forklift 1 is equipped with a cargo handling device H for handling cargo. The cargo handling device H includes an upper fork 2 and a lower fork 3 positioned above and below, and a driving force transmission mechanism C that transmits driving force to drive the upper fork 2 and the lower fork 3 using a single actuator A. In the example of Figures 4 to 6, the actuator A moves the upper fork 2 up and down, and the driving force transmission mechanism C moves the lower fork 3 up and down using the biasing force of the upper fork 2, which moves up and down due to the driving force of the actuator A.

[0031] The actuator A is, for example, a double-acting hydraulic cylinder 4 that extends and retracts parallel to the mast M. A cylinder tube 4A of the double-acting hydraulic cylinder 4 is attached to the frame 13, and the tip of the rod 4B is attached to the lift bracket 9. The actuator A may be another double-acting linear actuator such as an electric cylinder or a pneumatic cylinder. Alternatively, the actuator A may be configured as a mechanism using an electric or hydraulic rotary motor.

[0032] The upper fork 2 consists of a left fork 2L and a right fork 2R, and the lower fork 3 consists of a left fork 3L and a right fork 3R.

[0033] The mast M consists of a mast guide 11 that supports the lift bracket 9 and moves up and down, and an outer mast 12 that guides the mast guide 11 so that it can move up and down. Left and right linear guide rails G1 and G2 are attached to the top and bottom of the front of the lift bracket 9, and left and right support members 10L and 10R are attached to guide blocks that are guided by the upper and lower guide rails and can move left and right. The left fork 2L is attached to the support member 10L, and the right fork 2R is attached to the support member 10R.

[0034] (up and down movement of upper fork) By driving the actuator A, the upper fork 2 moves up and down together with the lift bracket 9, the mast guide 11, the guide rails G1 and G2, and the support members 10L and 10R.

[0035] (Upper fork width change) 4, 6 and 7, the distance between the left and right forks 2L and 2R of the upper fork 2 can be changed. The fork width adjustment mechanism E is composed of, for example, an electric cylinder 14, a rotating link 15, and operating rods 16L and 16R.

[0036] A cylinder tube 14A of the electric cylinder 14 is attached to the mast guide 11, and the tip of a rod 14B of the electric cylinder 14 is attached to a rotating link 15 that rotates around a rotation axis X in the front-to-rear direction. The tip of the rotating link 15 and the support members 10L, 10R are connected by operating rods 16L, 16R. Therefore, when the rod 14B of the electric cylinder 14 is moved forward or backward, the rotating link 15 rotates and the support members 10L, 10R move left and right along the guide rails of the linear guides G1, G2, thereby changing the distance between the left and right forks 2L, 2R.

[0037] The fork width adjustment mechanism E can change the spacing between the left and right forks 2L, 2R of the upper fork 2, which increases the size of the transported objects that can be loaded onto the upper fork 2, making it possible to transport a variety of transported objects. Also, since the actuator A moves the upper fork 2 up and down, even when the lower fork 3 is loaded with transported objects, the fork width adjustment mechanism E can be used to increase the spacing between the left and right forks 2L, 2R of the upper fork 2, so that the upper fork 2 can be lowered so as not to interfere with the transported objects on the lower fork 3.

[0038] (Up and down movement of the lower fork) 5 and 6, a middle portion 5C in the front-to-rear direction of the seesaw member 5 is supported by a bracket 20A, the bracket 20A is attached to a rear end portion V1 of the lower body, and a front end portion 5B of the seesaw member 5 is connected to the rear ends of the left and right forks 3L, 3R. A base end portion 7A of the link 7 is supported by a bracket 20B, and the bracket 20B is attached to a front end portion V2 of the lower body, which is the front end portion of the left and right legs UL, UR, and the front end portion 7B of the link 7 is connected to the front ends of the left and right forks 3L, 3R.

[0039] The seesaw member 5 is made up of a rear arm 8A and a front arm 8B that sandwich an intermediate portion 5C, and a parallel link mechanism is formed by the front arm 8B and a link 7 that is the opposite side of the front arm 8B. Therefore, when the upper fork 2 is lowered by actuator A and the pressing member 6 that descends with the upper fork 2 presses downward the roller 5D at the rear end 5A of the seesaw member 5, the seesaw member 5 rotates about the intermediate portion 5C, and the front arm 8B and link 7 that constitute the opposing links of the parallel link mechanism swing, causing the lower fork 3, consisting of the left fork 3L and the right fork 3R, to move up and down. The pressing member 6 may be one that moves up and down together with the upper fork 2, or it may be a separate part from the upper fork 2.

[0040] 5 and 6, the driving wheel O located at the rear end of the forklift 1 is in contact with the ground, and left and right driven wheels N attached to the middle portions of the left and right legs UL and UR in the fore-and-aft direction are also in contact with the ground. Behind the driven wheels N, there are the front arms 8B and brackets 20A of the seesaw member 5 that support the lower forks 3, and in front of the driven wheels N, there are the links 7 and brackets 20B that support the lower forks 3. Therefore, when a heavy load is lifted by the lower forks 3, the weight of the heavy load and the lower forks 3 is supported by the left and right legs UL and UR and the left and right driven wheels N located below, thereby improving load-bearing capacity and stability during transportation.

[0041] (Drive force transmission mechanism) In this embodiment, the driving force transmission mechanism C, which moves the lower fork 3 up and down by the biasing force of the upper fork 2, which moves up and down due to the driving force of the actuator A, is a seesaw member 5 supported at its intermediate part 5C in the fore-and-aft direction, with its rear end part 5A and front end part 5B swinging up and down.

[0042] Because the driving force is transmitted by the driving force transmission mechanism C, the two pairs of upper and lower forks 2, 3 can be driven by a single actuator A. Therefore, compared to a configuration with two actuators for raising and lowering the two pairs of upper and lower forks, the cargo handling device does not become larger in size and the manufacturing costs do not increase.

[0043] Furthermore, a linear actuator is used as the actuator A, and the lower fork 3 moves up and down in the opposite direction to the upper fork 2, which moves up and down to apply the biasing force, by the drive force transmission mechanism C. Therefore, the drive mechanism including the actuator and the drive force transmission mechanism C can be simplified, which reduces the number of parts and leads to space savings.

[0044] Further, the driving force transmission mechanism C is a seesaw member 5 whose rear end 5A and front end 5B are supported at a middle part 5C in the front-rear direction and which swings up and down, and the actuator A is a double-acting hydraulic cylinder 4 which moves the upper fork 2 up and down. Therefore, the rear end 5A of the seesaw member 5 is urged downward by the pressing member 6 which is driven by the double-acting hydraulic cylinder 4 and descends together with the upper fork 2 which is descending, and this, together with the weight of the upper fork 2, causes the front end 5B of the seesaw member 5 and the lower fork 3 to rise.

[0045] That is, the gravity of the upper fork 2, which is driven down by the double-acting hydraulic cylinder 4, also contributes to the biasing force of the pressing member 6 that biases the rear end 5A of the seesaw member 5 downward. Therefore, the capacity of the double-acting hydraulic cylinder 4 can be reduced, thereby reducing manufacturing costs.

[0046] Moreover, because the driving force transmission mechanism C is the seesaw member 5, it is possible to further simplify the driving force transmission mechanism C and ensure the operation of the driving force transmission mechanism C. Furthermore, by changing the ratio of the lengths of the rear arm 8A and the front arm 8B that sandwich the middle part 5C in the seesaw member 5, it is possible to adjust the output required for the double-acting hydraulic cylinder 4 and the lifting strokes of the upper fork 2 and the lower fork 3, thereby increasing the degree of freedom in design.

[0047] In addition, because a double-acting hydraulic cylinder 4 is used as actuator A, hydraulic force acts on both sides of the piston, allowing the lifting and lowering movements to be controlled hydraulically. By using hydraulic pressure, it is easy to generate power compared to its size, and it has excellent positioning accuracy and responsiveness.

[0048] The driving force transmission mechanism C may be configured, for example, by a rack and pinion or a chain drive mechanism, as long as it transmits driving force so that the upper fork 2 and the lower fork 3 are driven by a single actuator A. In a driving force transmission mechanism C configured by a rack and pinion, for example, the actuator A is a rotary actuator such as a geared motor, and the rotary actuator is connected to a pinion, so that the upper fork 2 and the lower fork 3 are driven in opposite vertical directions by two vertical racks that mesh with the pinion.

[0049] 5, in the rear arm 8A and the front arm 8B of the seesaw member 5, the length D1 of the rear arm 8A is longer than the length D2 of the front arm 8B (D1>D2). As a result, the biasing force of the pressing member 6 that biases the rear end portion 5A of the seesaw member 5 downward is increased at the front end portion 5B of the seesaw member 5. Therefore, the lower fork 3 can be lifted with a smaller biasing force.

[0050] 5, when the rear end portion 5A of the seesaw member 5 is not biased downward by the pressing member 6, the rear arm 8A tilts upward toward the rear, and the front arm 8B tilts upward toward the front. Therefore, compared to when the seesaw member is linear, the lowest position of the rear end portion 5A of the seesaw member 5 is not lowered, making it applicable even when there is a height restriction. Furthermore, since there is no need to secure a space to avoid interference with the rear end portion of the seesaw member, as is the case when the seesaw member is linear, the shape of the lower main body rear end portion V1 that supports the seesaw member 5 does not become irregular, making it easy to secure the required strength of the lower main body rear end portion V1 and preventing an increase in manufacturing costs.

[0051] Furthermore, when the rear end 5A is urged downward by the pressing member 6, the pressing member 6 and the roller 5D that is the rear end 5A of the seesaw member 5 come into contact with each other. However, as shown in FIG. 5, for example, there is also a state in which the pressing member 6 and the rear end 5A of the seesaw member 5 are spaced apart. In this state in which the pressing member 6 and the rear end 5A of the seesaw member 5 are spaced apart, the relationship between the loading and unloading operation by the upper fork 2 and the loading and unloading operation by the lower fork 3 can be arbitrarily cut off. Furthermore, by adjusting the distance between the pressing member 6 and the rear end 5A of the seesaw member 5, it is possible to adjust the downward stroke of the upper fork 2 that causes the lower fork 3 to start rising, the final rise height of the lower fork 3, and the like.

[0052] (A part that moves up and down in conjunction with the up and down movement of the lower fork) 4 to 6, left and right connecting links 17 are provided inside the front arm 8B of the seesaw member 5 in the left-right direction, and left and right up-and-down swinging bodies 18 are attached to the front ends of the connecting links 17, and the front ends of the up-and-down swinging bodies 18 are connected by horizontal rods 19.

[0053] Therefore, when the pressing member 6 descends from the position shown in Figure 5, the rear end 5A of the seesaw member 5 is forced downward by the pressing member 6, and the front end 5B of the seesaw member 5 and the lower fork 3 rise, the vertical swing body 18 swings upward, and the horizontal rod 19 rises so as to move away from the height of the upper surface of the lower fork 3.

[0054] When the rear end 5A of the seesaw member 5 is no longer forced downward by the pressing member 6, the front end 5B of the seesaw member 5 and the lower fork 3 descend to the position shown in Figure 5, and the vertical swing body 18 swings downward, so that the horizontal rod 19 also descends to the position shown in Figure 5.

[0055] [Examples of forklift operations within a funeral hall] (1) When the hearse arrives at the funeral home, the coffin W1 is placed on the upper fork 2 as shown in Figure 8. At that time, the width of the left and right forks 2L, 2R is adjusted to match the width of the coffin W1 using the fork width adjustment mechanism E shown in Figures 3 to 4 and 7.

[0056] (2) Forklift 1 is moved to the funeral hall and the funeral service is held.

[0057] (3) Move forklift 1 to the crematorium hall and say your final goodbyes to the body and the family.

[0058] (4) As shown in Figure 9, the forklift 1 is moved forward to the position shown in Figure 9, where the in-furnace cart W2 has been moved along the rails by the chain conveyor Y to the antechamber of the crematorium, and the coffin W1 is transported above the trivet on the in-furnace cart W2.

[0059] (5) The upper fork 2 is lowered to place the coffin W1 on the trivet, and then the forklift 1 is moved backward.

[0060] (6) The chain conveyor Y moves the furnace cart W2 carrying the coffin W1 into the crematorium, closes the fireproof door, and cremates the body.

[0061] (7) Open the fireproof door, move the in-furnace cart W2 to the front chamber of the crematorium using the chain conveyor Y, and wait for the specified cooling time for the crematorium.

[0062] (8) As shown in Figure 10, the forklift 1 is advanced toward the in-furnace cart W2 in the antechamber of the crematorium. At this time, the upper fork 2, which was lowered after step (5) was completed, is lowered in advance, and the fork width adjustment mechanism E is used to widen the gap between the left and right forks 2L and 2R so that the upper fork 2 does not interfere with the in-furnace cart W2. In the state shown in Figure 10, the in-furnace cart side engagement part J is engaged with the chain conveyor side engagement part I.

[0063] (9) The forklift 1 is further advanced toward the in-furnace cart W2 in the antechamber of the crematorium, and the lower fork 3 is raised as shown in Figure 11, causing the in-furnace cart W2 to be placed on the lower fork 3. When the lower fork 3 is raised as shown in Figure 11, the cross rod 19, which is a member that moves up and down in conjunction with the up and down movement of the lower fork 3, also rises. As the cross rod 19 rises, the disengagement piece K rises and the in-furnace cart side engagement part J descends, so the engagement between the chain conveyor side engagement part I and the in-furnace cart side engagement part J is released.

[0064] (10) The forklift 1 with the in-furnace cart W2 placed on the lower fork 3 is moved back from the chain conveyor Y, and after the tip attachment 24 is attached, it is moved to the bone collection room. Figure 12 shows the forklift 1 in the state of collecting bones.

[0065] As shown in Figures 3, 6, and 8, the forklift 1 according to the embodiment of the present invention has a space S between the left and right legs UL and UR. Therefore, as shown in Figures 10 and 11, the forklift can approach the chain conveyor Y that extends from the crematorium to the front room. This reduces the space required for the front room, which allows for a reduction in the floor area of ​​a newly constructed funeral home, for example, thereby saving space in the crematorium itself.

[0066] In the forklift trucks in the above embodiments, the upper forks are moved up and down by an actuator, and the drive force transmission mechanism moves the lower forks up and down by the biasing force of the upper forks, which are moved up and down by the driving force of the actuator. Depending on the load being transported, the forklift truck of the present invention may also be configured to move the lower forks up and down by an actuator, and the drive force transmission mechanism moves the upper forks up and down by the biasing force of the lower forks, which are moved up and down by the driving force of the actuator.

[0067] The above description of the embodiments is given by way of example only and is not intended to be limiting, and various improvements and modifications can be made without departing from the scope of the present invention. [Explanation of symbols]

[0068] 1 forklift 2 upper forks 2L Left fork 2R Right fork 3 Lower Fork 3L Left Fork 3R Right fork 4 Double acting hydraulic cylinder 4A Cylinder tube 4B Rod 5 Seesaw member 5A Rear end 5B Front end 5C Middle part 5D roller 6 pressing member 7 Link 7A Base end 7B Front end 8A Rear arm 8B Front arm 9 Lift bracket 10L, 10R Support member 11 Mast guide 12 Outer Mast 13 Frame 14 Electric cylinder 14A Cylinder tube 14B Rod 15 Rotating link 16L, 16R Operating rod 17 Connecting link 18 Vertical swing body 19 Horizontal rod 20A, 20B Bracket 21 Center cover 22 Side cover 23 Side panel 24 Tip attachment 25 Door A Actuator B Rear C Driving force transmission mechanism D1 Rear arm length D2 Front arm length E Fork width adjustment mechanism F Front G1, G2 linear guide H Load handling device I Chain conveyor side engagement part J Furnace truck side engaging part K Engagement release piece L Left M Mast N Driven wheels O Drive wheels P Operation panel Q Operation rod R Right S Space T Moving device UL,UR Legs V1 Lower rear end of main body V2 Lower front end of main body W1 Coffin W2 Furnace cart X Rotating axis Y Chain conveyor

Claims

1. A forklift that performs loading and unloading work, An upper fork and a lower fork positioned above and below; a driving force transmission mechanism that transmits driving force to drive the upper fork and the lower fork by a single actuator; Equipped with forklift.

2. the actuator moves one of the upper fork and the lower fork up and down, the driving force transmission mechanism moves the other of the upper fork and the lower fork up and down by the biasing force of the one fork which moves up and down by the driving force of the actuator, 2. The forklift according to claim 1.

3. the actuator is a linear actuator that expands and contracts in parallel with the mast, The one fork moves up and down in a direction toward or away from the other fork so as to apply the biasing force, The other fork is moved up and down in a direction opposite to the direction in which the one fork moves up and down by the driving force transmission mechanism.

3. The forklift according to claim 2.

4. the drive force transmission mechanism is a seesaw member whose rear end and front end are supported at a middle portion in the front-rear direction and which swings up and down, the linear actuator is a double-acting actuator that moves the upper fork up and down, a pressing member that is driven by the double-acting actuator to descend together with the upper fork, and the rear end of the seesaw member is urged downward, including by the weight of the upper fork, thereby causing the lower fork to rise together with the front end of the seesaw member; 4. The forklift according to claim 3.

5. The double-acting actuator is a double-acting hydraulic cylinder.

5. The forklift according to claim 4.

6. a rear arm and a front arm sandwiching the intermediate portion of the seesaw member, the rear arm having a length longer than the front arm; 5. The forklift according to claim 4.

7. a rear arm and a front arm sandwiching the intermediate portion of the seesaw member, the rear arm tilting upward at the rear and the front arm tilting upward at the front when the rear end portion is not biased downward by the pressing member; 7. The forklift according to claim 4 or 6.

8. There are a state in which the pressing member and the rear end of the seesaw member are in contact with each other, and a state in which the pressing member and the rear end of the seesaw member are separated from each other.

7. The forklift according to claim 4 or 6.

9. The upper fork further includes a fork width adjustment mechanism for changing the distance between the left and right forks. The forklift according to any one of claims 1 to 6.

Images