Pallet Lift

Abstract

To provide a pallet lift in which a pallet can be widely applied, which can lift the pallet with the pallet lift itself, and which can move with the pallet lifted.SOLUTION: A pallet lift A comprises a pallet supporting member 1, an expansion / contraction driving member, caster members 20, parallel link members 30, and cam members 40, where the pallet supporting member arranged along a side girder P1 of a pallet P and expanding / contracting along the girder P1, the expansion / contraction driving member to expand / contract the pallet supporting member 1, the caster member provided to be adjacent to both ends 3, 13 of the pallet supporting member 1 and with running wheels 29, the parallel link member to connect the ends 3, 13 of the pallet supporting member 1 and the caster members 20, and to raise / lower the pallet supporting member 1, and the cam member attached to the lower link arm of the parallel link member 30 and having a clamping surface to be in contact with or separated from an outer end face P2 of the side girder P1 of the pallet P.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a pallet lift that can be attached directly to a logistics pallet and can move cargo using the pallet alone, without using a forklift. [Background technology]

[0002] In manufacturing plants, pallets P are used to carry cargo N, such as parts, semi-finished products, and finished products, and to transport them to the next process. The pallets P carrying these cargo N are then transported to a designated location by a forklift. The emptied pallets P are then collected and returned to their original location. In this way, a forklift is essential for transporting cargo N using pallets P, and it was previously impossible to transport cargo N using a pallet alone. However, pallets P carrying cargo N are stored side by side in a warehouse, for example, and even if one tries to take out a pallet P lined up at the back, the forklift cannot reach the storage location. To take out a pallet P at the back, it is necessary to move the pallets P at the front to another location and create an aisle that allows the forklift to reach that location, which takes time for the transport work.

[0003] In response to this, a pallet lift 100 has been proposed that is attached directly to a pallet P and moves the pallet P alone without using a forklift (Patent Document 1). This pallet lift 100 is composed of a pallet support member 110 and traveling wheels 120, and the pallet support member 110 is detachably attached to four locations on the front, back, left and right of the pallet P by clamping the ends of two inner beams p20 made of square timber that pass from front to back inside the pallet P and the front and rear edge boards p30 that are stretched at right angles to these, and the traveling wheels 120 are journaled on the underside of the pallet support member 110 so as to be rotatable 360°. A pallet P to which the pallet lift 100 configured in this way is attached can be moved by itself in a loaded state through narrow passages in the storage area of ​​the pallet P without a forklift. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Publication number 03-019837 Summary of the Invention [Problem to be solved by the invention]

[0005] However, since the pallet lift 100 is not structured to lift the pallet P by itself, in order to attach the pallet lift 100 to the four left and right ends of the front and rear ends of the pallet P, it is necessary to lift the pallet P by some method (for example, a jack) when it is empty, or when it is carrying cargo N, and create a gap between the pallet P and the floor surface G for the attachment, which makes the attachment troublesome. Also, there are various types of pallets P, such as those made of wood or resin, two-way insertion that allows forks to be inserted from two directions, and four-way insertion that allows forks to be inserted from four directions. There are also various sizes, such as those with one inner girder p20 made of vertical frame square timber as shown in Figure 18, and those with two as shown in Figure 16. Conventional pallet lifts 100 must be attached to the inner girder p20 as shown in Figure 16, and therefore cannot be attached to pallets with only one inner girder p20 as shown in Figure 18, limiting the types of pallets P that can be used.

[0006] The present invention has been made in consideration of the problems with conventional pallet lifts, and the object of the present invention is to provide a pallet lift which has a wider range of application than conventional ones, is capable of lifting a pallet by itself, and can be moved in that state. [Means for solving the problem]

[0007] The pallet lift A described in claim 1 (embodiment 1: Figs. 1 to 9) is A pallet support member 1 including a support body 2 arranged along a girder p1 on a side surface of a pallet P and a slide member 12 arranged to be inserted and removed horizontally relative to the support body 2; An expansion and contraction drive member 15 that is attached to the slide member 12 and moves the support body 2 in the insertion and removal direction; Caster members 20 each provided adjacent to both ends 3 and 13 of the pallet support member 1 and each having a running wheel 29; a parallel link member 30 that connects the ends 3·13 of the pallet support member 1 to the caster members 20 and raises and lowers the pallet support member 1 relative to the caster members 20; Any of the parallel link members 30 Link arm 35(31) and a cam member 40 having a clamping surface 45 that comes into contact with and separates from the outer end surface p2 of the girder p1 on the side surface of the pallet P. The lower end of the link arm 35 (31) to which the cam member 40 is attached is pivotally attached to each of the ends 3 and 13 of the pallet support member 1 so as to be rotatable in the vertical direction, and the pivot portion S of the link arm 35 (31) is formed so as to be positioned below the abutment point Q1 (force point described later) of the cam member 40 with the outer end surface p2 of the girder p1 on the side of the pallet P.

[0008] The pallet lift B described in claim 2 (embodiment 2: Figs. 10 and 11) is A pallet support member 1 including a support body 2 arranged along a girder p1 on a side surface of a pallet P and a slide member 12 arranged to be inserted and removed horizontally relative to the support body 2; An expansion and contraction drive member 15 that is attached to the slide member 12 and moves the support body 2 in the insertion and removal direction; Caster members 20 each provided adjacent to both ends 3 and 13 of the pallet support member 1 and each having a running wheel 29; a parallel link member 30 that connects the ends 3·13 of the pallet support member 1 to the caster members 20 and raises and lowers the pallet support member 1 relative to the caster members 20; and a pad member 41 having a clamping surface 45 attached to any one of the link arms 35 (31) of the parallel link member 30 and whose entire surface comes into contact with and separates from the outer end surface p2 of the girder p1 on the side surface of the pallet P. The link arm 35 (31) to which the pad member 41 is attached includes a pad arm 37 extending obliquely upward from the end portion on the pallet support member 1 side toward the outer end surface p2 of the girder p1 on the side surface of the pallet P, The pad arm 37 has a pad pivot hole 37a for pivotally mounting the pad member 41 so as to be vertically swivellable. The extended portion of the pad arm 37 of the link arm 35 (31) is pivotally attached to each of the ends 3 and 13 of the pallet support member 1 so as to be rotatable in the vertical direction, and the pivot portion S of the link arm 35 (31) is formed so as to be positioned below the pad pivot hole 37a of the pad arm 37 (force point Q2 described later).

[0009] The pallet lift C described in claim 3 (embodiment 3; Figs. 12 to 14) is A pallet support member 1 including a support body 2 arranged along the outer surface of a block p4 provided at each of the four corners of a pallet P and a slide member 12 provided so as to be inserted and removed horizontally relative to the support body 2; an expansion and contraction driving member 15 that is attached to the slide member 12 and moves the support body 2 in the insertion and removal direction; A caster member 20 provided adjacent to an end portion 13 of the slide member 12 located outside the block p4 of the pallet P and equipped with a running wheel 29; A parallel link member 30 that connects the end portion 13 of the slide member 12 and the caster member 20 and raises and lowers the pallet support member 1 in the vertical direction relative to the caster member 20; a cam member 40 attached to any one of the link arms 35 (31) of the parallel link member 30 and having a clamping surface 45 adapted to come into contact with and separate from an outer end surface p5 of the block p4 of the pallet P; a clamping member 50 which is attached to the support body 2, comes into contact with and separates from an inner end face p6 of the block p4 opposite to an outer end face p5 of the block p4 on the cam member 40 side, and clamps both inner and outer end faces p5 and p6 of the block p4 between the block p4 and the cam member 40, The lower end of the link arm 35 (31) to which the cam member 40 is attached is pivotally attached to each of the ends 3 and 13 of the pallet support member 1 so as to be rotatable in the vertical direction, and the pivot portion S of the link arm 35 (31) is formed so as to be positioned below the abutment point Q1 (force point described later) of the cam member 40 with the outer end surface p2 of the girder p1 on the side of the pallet P.

[0010] The pallet lift D described in claim 4 (embodiment 4: FIG. 15) is A pallet support member 1 including a support body 2 arranged along the outer surface of a block p4 provided at each of the four corners of a pallet P and a slide member 12 provided so as to be inserted and removed horizontally relative to the support body 2; An expansion and contraction drive member 15 that is attached to the slide member 12 and moves the support body 2 in the insertion and removal direction; A caster member 20 provided adjacent to an end portion 13 of the slide member 12 located outside the block p4 and equipped with a running wheel 29; a parallel link member 30 that connects the end portion 13 located outside the block p4 to the caster member 20 and raises and lowers the pallet support member 1 in the vertical direction relative to the caster member 20; a pad member 41 attached to any one of the link arms 35 (31) of the parallel link member 30 and having a clamping surface 45 whose entire surface comes into contact with and separates from an outer end surface p5 of the block p4 of the pallet P; a clamping member 51 attached to the support body 2, the entire surface of which comes into contact with and separates from an inner end surface p6 of the block p4 located opposite the outer end surface p5, and which clamps the inner and outer end surfaces p5 and p6 of the block p4 between the pad member 41 and the clamping member 51; The link arm 35 (31) to which the pad member 41 is attached includes a pad arm 37 extending obliquely upward from the end portion on the slide member 12 side toward the outer end surface p5 of the block p4 of the pallet P, The pad arm 37 has a pad pivot hole 37a for pivotally mounting the pad member 41 so as to be vertically swivellable. The portion of the link arm 35 (31) from which the pad arm 37 extends is pivotally attached to the end 13 of the slide member 12 so as to be rotatable in the vertical direction, and the pivot portion S of the link arm 35 (31) is formed so as to be positioned below the pad pivot hole 37a of the pad arm 37 (force point Q2 described later).

[0011] Claim 5 provides the pallet lifts A to D according to any one of claims 1 to 4, The telescopic drive member 15 is characterized by being composed of a rotatable screw member 16 arranged horizontally on the slide member 12, and a nut member 18 screwed onto the screw member 16 so as to be freely threaded forward and backward and attached to the support body 2.

[0012] Claim 6 provides the pallet lift C according to claim 3, The clamping surface 55 of the clamping member 50 is formed in a convex arc shape so as to come into point contact with the end surface p5 of the clamping member 50 side.

[0013] Claim 7 provides the pallet lift D according to claim 4, The clamping receiving member 51 is pivotally attached to a spacer 58 attached to the support main body 2 so as to be able to swing up and down, and is characterized by having a receiving pad member 52 whose entire surface contacts the inner end face p6 of the block p4. Effect of the Invention

[0014] According to the first or second embodiment of the present invention, the pallet lifts A and B are installed along the girders p1 on both side surfaces of the pallet P, and when the telescopic drive member 15 is operated in this state, the cam members 40 or pad members 41 will clamp and lift the pallet P. When the pallet P is pulled after being lifted from the floor surface G, the pallet P will move freely by the traveling wheels 29. The pallet lifts A and B of the first or second embodiment can be used with pallets P having outer end faces p2 at the four corners with which the cam members 40 or pad members 41 can abut, whether the pallet P is inserted in two directions or in four directions, and can be used with pallets P having one or two inner girders P20.

[0015] Furthermore, according to the third or fourth embodiment, the pallet lifts C and D are installed along the blocks p4 at the four corners of the pallet P, and when the telescopic drive member 15 is operated, the cam member 40 or the pad member 41 cooperates with the clamping receiving members 50 and 51 to similarly lift the pallet P, thereby enabling the pallet P to be moved freely. In this case, any size of pallet P can be accommodated as long as it has blocks p4 at its four corners. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a plan view showing an installation state of a pallet lift according to a first embodiment of the present invention. [Diagram 2] 2 is a front view of the pallet in FIG. 1 before it is lifted up, taken along the arrow XX. [Diagram 3] 2 is a front view of the pallet in FIG. 1 when it is lifted up, taken along the arrow XX. [Figure 4] FIG. 2 is an enlarged plan view of the pallet lift of FIG. 1, with some parts omitted. [Diagram 5] FIG. 5 is a front view of FIG. [Figure 6] 5(a) is a left side view of FIG. 5, and FIG. [Figure 7] FIG. 2 is an exploded perspective view of FIG. [Figure 8] FIG. 3 is a partially enlarged view of FIG. 2 before lifting. [Figure 9]FIG. 4 is a partial enlarged view of the lift state of FIG. 3. [Figure 10] FIG. 11 is a partial plan view of the second embodiment. [Figure 11] FIG. 11 is a front view of FIG. [Figure 12] FIG. 11 is a plan view showing the installation state of the pallet lift of the third embodiment. [Figure 13] FIG. 13 is a front view of the state before the pallet in FIG. 12 is lifted. [Figure 14] FIG. 14 is a partially enlarged view of FIG. [Figure 15] FIG. 13 is a partially enlarged view of the fourth embodiment. [Figure 16] FIG. 13 is a perspective view illustrating a state in which a conventional example is used. [Figure 17] FIG. 17 is a perspective view of the conventional pallet lift of FIG. 16. [Figure 18] This is a perspective view of a two-way pallet. [Figure 19] This is an oblique view of a four-way pallet. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The present invention will be described below with reference to the drawings. There are four types of pallet lifts A to D of the present invention. In the first and second embodiments (Figs. 1 to 11), the pallet support members 1, which are the main frames of the pallet lifts A to D, are arranged over the entire length of the girders p1 on both sides of the pallet P, and in the third and fourth embodiments (Figs. 12 to 15), they are arranged individually on blocks p4 at the four corners of the pallet P. In the first and third embodiments, a cam member 40 is used as a member for clamping and lifting the pallet P, and in the second and fourth embodiments, a pad member 41 is used. In explaining the pallet lifts A to D of the present invention, the explanation will be given in order starting from the first embodiment. In explaining the second and subsequent embodiments, however, explanations of parts that overlap with the first embodiment will be omitted as a general rule, and the explanations of the first embodiment will be used as a general rule in explaining the second and subsequent embodiments.

[0018] Pallets P to which the pallet lifts A to D of the present invention are applied are loading platforms for carrying cargo N and are used in logistics. In addition to the most typical flat pallet, there are many other types such as box pallets and sheet pallets. Pallets P to which the pallet lifts A to D of the present invention are applied are primarily flat pallets that do not have a superstructure and have insertion ports for the forks of a forklift. Of course, they are not limited to flat pallets. Pallets P are often made of wood, but some are made of synthetic resin. The structure of the pallet P to which the pallet lifts A to D of the present invention can be applied includes, as shown in Figure 18, a structure in which side girders p1 and a central girder p20 made of square timber are attached above and below the lateral frames, with edge boards p30 and deck boards p31 attached above and below the lateral frames, as well as a structure as shown in Figure 19, in which blocks p4 made of square timber are attached to the four corners, and another block p40 is attached on the inside, with edge boards p30 and deck boards p31 attached above and below the block p40.

[0019] The pallet lift A of the first embodiment is composed of a pallet support member 1, an extendable drive member 15, caster members 20, parallel link members 30, and a cam member 40. The pallet lift A is disposed over the entire length along the girders p1 on both side surfaces of the pallet P, and is capable of lifting up the pallet P while clamping the outer end portions p2 of the girders p1 on both side surfaces of the pallet P from both sides, and moving in that state.

[0020] As described above, the pallet support member 1 is a member disposed along the beams p1 on both side surfaces of the pallet P, and is provided with caster members 20 adjacent to both ends 3, 13. The pallet support member 1 is composed of two members: a support body 2 and a slide member 12. The support body 2 is a rectangular cylindrical member having a cavity with a vertically long cross section over its entire length in the longitudinal direction, and the opening of one end (this part is called the insertion side end 5) is designed to insert and remove the slide member 12. The other end 3 is the end to which one caster member 20 is attached, and the upper and lower parts of the end 3 on the caster member 20 side are provided with the body side upper pivot hole 4a and the body side lower pivot hole 4b for pivoting the stepped upper and lower pins 60 and 70 described later (Fig. 7). The body side upper pivot hole 4a and the body side lower pivot hole 4b are provided on a perpendicular line perpendicular to the longitudinal direction of the support body 2. The insertion side end 5 is provided with round holes 6 on the top, bottom, left and right to fasten the nut members 18 described later. The entire length of the support body 2 is shorter than the length of the girder p1 on the side of the pallet P.

[0021] The slide member 12 is a member inserted into and removed from the insertion end 5 of the support body 2, and is composed of a removable member body 12a having a U-shaped cross section with a width and height that allows it to be inserted into and removed from the opening of the insertion end 5, a screw fixing plate 12b that is provided at the insertion end of the removable member body 12a and fixes a screw receiving member 16d of the insertion end of the screw member 16 described later, a holding block 14 that is provided at the end 13 opposite to the insertion end and rotatably holds the telescopic driving member 15, and a square tube member 19 that surrounds the periphery of the holding block 14 via the removable member body 12a. Since the screw receiving member 16d only needs to be able to rotatably hold the insertion end of the screw member 16, here it is composed of a washer fixed to the screw fixing plate 12b and a stepped tube member into which the insertion end of the screw member 16 is inserted and rotatably fitted into the washer. The holding block 14 is divided into an upper half and an lower half, and a rotation holding hole 14h for supporting the neck portion 16b of the screw member 16 so that it can rotate is formed at the mating portion between the upper and lower blocks 14U and 14D. The square tube member 19 is a tube that is short in front-to-back length and long in the up-down direction, into which the removable member main body 12a is inserted, and furthermore, the retaining block 14 is fitted inside the removable member main body 12a, and these are bolted together to form a single unit (Figure 6(b)).

[0022] The telescopic drive member 15 is composed of the screw member 16 and the nut member 18. The screw member 16 is composed of the neck portion 16b, the head portion 16a, and the screw portion 16c, and the diameter of the neck portion 16b is smaller than the diameters of the head portion 16a and the screw portion 16c, so that the screw member 16 will not fall out of the rotation holding hole 14h of the holding block 14. The head portion 16a is formed, for example, in a hexagonal shape so that an electric box wrench can be attached. The screw portion 16c has a male thread engraved on its outer periphery over its entire length, and its insertion end is attached to the screw fixing plate 12b of the slide member 12 via a screw receiving member 16d. A nut member 18 attached to the support portion main body 2 is screwed onto the screw portion 16c so as to be capable of being screwed forward and backward. The nut member 18 is movably disposed inside the insertion / removal member main body 12a having the U-shaped cross section.

[0023] The caster member 20 is composed of a running wheel 29 and a base 21 which supports the running wheel 29 and to which the upper end of the parallel link member 30 is pivotally attached. The base 21 is composed of a horizontal plate 22 and a vertical plate 23 which is erected vertically in the center of the upper surface of the horizontal plate 22, and the running wheel 29 is attached to the underside of the horizontal plate 22. Base-side pivot holes 23a and 23b to which the upper end of the parallel link member 30 is pivotally attached are drilled above and below the vertical plate 23. The base-side pivot holes 23a and 23b are provided on a perpendicular line erected on the horizontal plate 22, and the interval between them is equal to the interval between the upper and lower pivot holes 14a and 14b of the holding block 14 and the main body-side upper and lower pivot holes 4a and 4b of the end portion 3 of the support main body 2.

[0024] The parallel link member 30 is a pair of flat plate members provided above and below (in this embodiment, the same flat plate members are also provided on the left and right), and these flat plate members are referred to as link arms 31 and 35. The upper side is referred to as upper link arm 31, and the lower side is referred to as lower link arm 35. Link arms 31 and 35 have round pivot holes formed in their upper, middle and lower end portions. The round hole at the upper end portion of upper link arm 31 is referred to as upper link first pivot hole 31a, the round hole at the lower end portion is referred to as upper link second pivot hole 31b, the round hole at the upper end portion of lower link arm 35 is referred to as lower link first pivot hole 35a, and the round hole at the lower end portion is referred to as lower link second pivot hole 35b. The round holes at the middle portions are referred to as upper link intermediate round hole 31c and lower link intermediate round hole 35c, respectively.

[0025] The cam member 40 is a fan-shaped member, and its convex arc portion is the clamping surface 45, and triangular unevenness is formed over the entire width of the member. Round holes are formed in the main portion and in the vicinity of the clamping surface 45. The round hole in the main portion is the cam fixing round hole 40c, and the round hole in the vicinity of the clamping surface 45 is the fulcrum hole 40b, which is the fulcrum S that is the center of rotation of the cam movement. In this embodiment, two cam members 40 are used side by side on the left and right. In this embodiment, the radius R from the center of the fulcrum hole 40b to the clamping surface 45 is shorter for the radius R2 closer to the fulcrum hole 40b of the clamping surface 45 than for the radius R1 farther away. In other words, the radius R gradually increases as it moves away from the fulcrum hole 40b (FIG. 7).

[0026] The cam member 40 and the parallel link member 30 installed at the front and rear are attached to the end 13 of the slide member 12 and the end 3 of the support body 2 by stepped upper and lower pins 60 and 70, respectively. The stepped upper pin 60 has a thick diameter portion 61 equal to the thickness of the vertical plate 23 of the base 21, a link side shaft portion 63 protruding from one side of the thick diameter portion 61, and a component side shaft portion 65 protruding from the other side, while the stepped lower pin 70 has a narrow thick diameter portion 71, a link side shaft portion 73 protruding from one side of the thick diameter portion 71, and a component side shaft portion 75 protruding from the other side (Figure 7).

[0027] As can be seen from Figure 7, the link arms 31 and 35 are members that connect the ends 3 and 13 of the pallet support member 1, i.e., the end 3 of the support body 2 and the end 13 of the slide member 12, to the vertical plates 23 of the front and rear caster members 20, respectively. The mounting structure for the upper end portions of the link arms 31 and 35 to the vertical plate 23 and the mounting structure for the cam member 40 (described later) to the link arms 31 and 35 are symmetrical front to back on the support main body 2 side and the slide member 12 side, but have the same structure. However, the mounting structure for the lower end portions of the link arms 31 and 35 on the support main body 2 side and the slide member 12 side are slightly different from each other. First, the mounting structure of the link arms 31 and 35 on the slide member 12 side will be described, and in the description of the support portion main body 2 side, differences from the mounting structure on the slide member 12 side will be mainly described.

[0028] The mounting structure of the upper end portions of the link arms 31 and 35 on the slide member 12 side to the vertical plate 23, and the connection structure of the lower end portions of the link arms 31 and 35 to the end portion 13 of the slide member 12 will be described below. The upper end portions of a pair of left and right upper link arms 31 are arranged to sandwich the upper end portion of the vertical plate 23 of the base 21 from both sides, and the upper link first pivot holes 31a in the upper end portions of both upper link arms 31 are pivotally attached to the base side pivot hole 23a at the upper end of the vertical plate 23 by a bolt so that they can swing. The upper end portions of a pair of left and right lower link arms 35 are arranged to sandwich the lower end portion of the vertical plate 23 of the base 21 from both sides, and the lower link first pivot hole 35a in the upper end portions of the lower link arms 35 is pivotally attached to the base side pivot hole 23b at the lower end of the vertical plate 23 by a bolt so that it can swing.

[0029] The lower end portions of the pair of left and right upper link arms 31 are arranged to sandwich a spacer ring 68 having a thickness equal to the thickness of the vertical plate 23 of the base 21 from both sides, and the link side shaft portion 63 of the stepped upper pin 60 is inserted so as to penetrate the upper link second pivot hole 31b of both upper link arms 31 and the spacer ring 68. Then, the end face of the wide large diameter portion 61 of the stepped upper pin 60 contacts the side of the upper link arm 31 on the slide member 12 side, and these are nut-fastened by the end face of the wide large diameter portion 61 and a nut. This nut fastening is performed so that the upper link second pivot hole 31b swings and rotates around the link side shaft portion 63. The member side shaft portion 65 of the stepped upper pin 60 extending on the opposite side to the link side shaft portion 63 is inserted so as to penetrate the upper pivot holes 19a inside and outside the square tube member 19, the upper pivot hole 14a of the retaining block 14, and the through hole of the removable member main body 12a, and is bolted in place via a washer (Figure 6(b)).

[0030] The lower end portions of the pair of left and right lower link arms 35 are arranged to sandwich from both sides one cam member 40 having a thickness equal to that of the vertical plate 23 of the base 21, and the other cam member 40 is further arranged on the lower end side surface of the lower link arm 35 on the slide member 12 side. In other words, the lower ends of the pair of left and right lower link arms 35 / 35 and the two left and right cam members 40 / 40 are arranged alternately (FIG. 6(b)).

[0031] Then, the link side shaft portion 73 of the stepped lower pin 70 is inserted so as to penetrate through the lower link second pivot holes 35b of both lower link arms 35 and the fulcrum holes 40b of both cam members 40, and the end face of the narrow wide large diameter portion 71 of the stepped lower pin 70 comes into contact with the side face of the cam member 40 on the slide member 12 side, and these are nut-fastened by the end face and the nut. This nut fastening is performed so that both lower link arms 35 and both cam members 40 swing up and down around the link side shaft portion 73. This link side shaft portion 73 of the stepped lower pin 70 becomes the fulcrum S for the swinging rotation of the cam member 40, as described later.

[0032] The member-side shaft portion 75 of the stepped lower pin 70, which extends on the opposite side to the link-side shaft portion 73, is inserted through the lower pivot holes 19b inside and outside the square tube member 19, the lower pivot hole 14b of the holding block 14, and the through hole of the removable member main body 12a, and is bolted via a washer (FIG. 6(b)). That is, the stepped lower pin 70, which serves as the fulcrum S of the cam member 40 on the slide member 12 side, has the lower link second pivot holes 35b of both lower link arms 35 and the fulcrum holes 40b of both cam members 40 attached to it at the link-side shaft portion 73, and the member-side shaft portion 75 has the lower pivot holes 19b inside and outside the square tube member 19, the lower pivot hole 14b of the holding block 14, and the through hole of the removable member main body 12a attached to it.

[0033] The above-mentioned cam members 40 may be attached to either the upper or lower link arms 31, 35 as long as the following conditions are satisfied, but in this specification it is attached to the lower link arm 35. When mounting the cam member 40 to the upper link arm 31, the upper and lower shoulder pins 60, 70 are installed upside down. When attaching the cam member 40 to the lower link arm 35 as described above, the fixing round hole 40c of the cam member 40 and the lower link intermediate round hole 35c of both lower link arms 35 are fixed with a bolt, and both cam members 40 are fixed integrally at two points, that is, the lower link intermediate round hole 35c of both lower link arms 35 and the above-mentioned lower link second pivot hole 35b.

[0034] On the support body 2 side, the connection structure between both link arms 35 and both cam members 40, the connection structure between both link arms 35 and the vertical plate 23 of the caster member 20, and the connection structure between both link arms 35 and the stepped upper and lower pins 60 and 70 are the same as above, but the member-side shaft portions 65 and 75 of the stepped upper and lower pins 60 and 70 are simply bolted via washers to the body-side upper and lower pivot holes 4a and 4b provided at the end 3 of the support body 2. On the support body 2 side as well, the stepped lower pin 70 serves as the fulcrum S of the cam member 40.

[0035] Next, we will explain how to use the pallet lift A. As shown in Figure 1, the pallet lift A is placed along the girder p1 on the side of the pallet P. In this state, the pallet P is placed on the floor surface G in a loaded state (Figure 2). At this point, the clamping surface 45 of the cam member 40 of the pallet lift A is away from the outer end surface p2 of the girder p1 of the pallet P. In this state, the electric box wrench is attached to the head 16a of the screw member 16, and the electric box wrench is rotated. This rotates the screw member 16, and the support body 2 is pulled toward the head 16a via the nut member 18 screwed onto the screw portion 16c. Then, the clamping surface 45 of the cam member 40 comes into contact with the outer end surface p2 of the girder p1 on the side surface of the pallet P at the abutment point Q1.

[0036] When the electric box wrench is further operated from this state, the support body 2 is further drawn toward the head 16a, and the outer end surface p2 of the pallet P presses the cam member 40 horizontally at the abutment point Q1. At this time, a horizontal pressing force F is generated on the cam member 40 at the contact point Q1 as shown in Figure 8. If this contact point Q1 is considered to be the "point of force" where the pressing force F is applied, then the stepped lower pin 70 inserted into the fulcrum hole 40b of the cam member 40 becomes the "fulcrum S," and the first lower link pivot hole 35a at the upper end of the lower link arm 35 on the opposite side becomes the "point of action K."

[0037] Furthermore, the distance L2 from the floor surface G to the abutment point Q1 is significantly higher than the distance L1 from the floor surface G to the fulcrum S. In other words, since the fulcrum S of the cam member 40 is located below the abutment point Q1, when a pressing force F is applied to the abutment point Q1, which is the "point of force," according to the principle of leverage, an upward component force F1 in a direction perpendicular to the line connecting the fulcrum S and the abutment point Q1 tries to rotate the line connecting the fulcrum S and the abutment point Q1 upward (counterclockwise in the figure) around the "fulcrum S." Since the cam member 40 and the lower link arm 35 are fixed integrally, a downward rotational force is applied to the bolt inserted into the first lower link pivot hole 35a of the lower link arm 35 as a reaction thereto.

[0038] The lower link first pivot hole 35a is pivotally attached to the lower base pivot hole 23b on the vertical plate 23 of the base 21 of the caster member 20 by a bolt. The caster member 20 is in contact with the floor surface G, and the base-side pivot hole 23b on the lower side of the base 21 does not move in the vertical direction, so the fulcrum S of the cam member 40 is lifted up as a reaction to the downward rotation force applied to the bolt inserted into the lower link first pivot hole 35a. Since the cam member 40 and the lower link arm 35 are integrated, the contact point Q1 is lifted up together with the fulcrum S, with the base-side pivot hole 23b (lower link first pivot hole 35a) on the lower side of the vertical plate 23 of the base 21 of the caster member 20 as the center of rotation.

[0039] This cam member 40 is provided on both ends 3, 13 of the pallet support member 1 and engages with both outer end faces p2 of the girder p1 on the side of the pallet P. Therefore, when the head 16a of the screw member 16 of this pallet lift A is operated, both cam members 40 rotate simultaneously in the upward direction, and the girder p1 on one side of the pallet P is lifted.

[0040] And because the upper and lower link arms 31, 35 are parallel links, the stepped upper and lower pins 60, 70 inserted into the upper and lower link second pivot holes 31b, 35b of the upper and lower link arms 31, 35 move vertically upward as the link arms 31, 35 are lifted and rotated. Because these stepped upper and lower pins 60, 70 are pivotally mounted to both ends of the pallet support member 1, the pallet P clamped between the support member 1 and the cam member 40 also moves vertically upward as the link arms 31, 35 are lifted and rotated. In other words, the pallet P is lifted. Since the clamping surface 45 of the cam member 40 is formed in a convex arc shape, the abutment point Q1 moves downward as the contact point Q1 of the cam member 40 is lifted.

[0041] Then, when the pallet lift A is raised to a specified height, the electric box wrench is stopped and removed from the head 16a. When the electric box wrench is removed, the weight of the load N and the pallet P is applied to the cam member 40, which tries to rotate the cam member 40 in the reverse direction (downward direction), but the distance between the abutment points Q1 of the front and rear cam members 40 does not increase because it is fixed by the stopped nut member 18, and the clamping surface 45 strongly abuts against the outer end face p2, preventing the cam member 40 from rotating in the reverse direction, and maintaining the lifted state of the pallet P. Note that the unevenness of the clamping surface 45 bites into the outer end face p2 of the girder p1 on the corresponding side of the pallet P, effectively holding the position. In other words, the pallet P does not slip down even when the electric box wrench is removed.

[0042] When the lifting operation of one pallet lift A is completed, the same operation is performed to lift the girder p1 on the opposite side of the pallet P. When the lifting of the pallet P is completed, the pallet P is pulled (or pushed) to move. Once the pallet P has been moved to the destination, an electric box wrench is attached to the head 16a of the screw member 16, and when the nut member 18 is rotated in a direction to loosen it, the cam member 40 rotates in the reverse direction in the unloading direction, lowering the pallet P to the floor surface G. When the electric box wrench is further operated, the cam member 40 is detached from the pallet P.

[0043] Although the radius R from the fulcrum S of the cam member 40 to the clamping surface 45 is not shown, it may be the same radius from the top to the bottom of the clamping surface 45, or it may be gradually decreased from the top to the bottom as shown.

[0044] Next, a second embodiment will be described. The second embodiment is an example in which a pad member 41 is used instead of the cam member 40. Accordingly, the shape of the lower link arm 35 differs from that of the lower link arm 35 of the first embodiment. (Although not shown, the upper link arm 31 may be used as described above.) The rest of the structure is the same as that of the first embodiment. The lower link arm 35 of the second embodiment is formed in an L shape with a pad arm 37 extending obliquely upward from the end on the lower link second pivot hole 35b side (in other words, obliquely upward in the direction of the outer end face p2 of the girder p1 of the side face of the pallet P). A pad pivot hole 37a is provided at the tip of the pad arm 37. The distance L2 from the floor surface G to the pad pivot hole 37a (point of action K) is greater than the distance L1 from the floor surface G to the lower link second pivot hole 35b (fulcrum S).

[0045] The pad member 41 is composed of a pad mounting portion 42 and a pad 43. The pad mounting portion 42 is composed of a pad mounting surface member 42a and a pair of pivotal mounting plates 42b provided perpendicularly thereto, and mounting holes 42h are formed in the pivotal mounting plates 42b. The pad 43 is made of, for example, a hard rubber plate and is attached to the pad mounting surface material 42a. The pivot plate 42b of the pad mounting portion 42 faces the tip side of the pad arm 37 extending from the lower link arm 35, and a bolt is inserted into the pad pivot hole 37a of the pad arm 37 and the mounting hole 42h of the pivot plate 42b, so that the pad is pivotally mounted so as to be swivelable in the vertical direction.

[0046] Next, the operation of the second embodiment will be described. As in the first embodiment, the pallet lift B is placed along the girder p1 on the side of the pallet P. In this state, the clamping surfaces 45 of the front and rear pad members 41 of the pallet lift B are separated from the outer end surface p2 of the girder p1 on the side of the pallet P. Then, as in the first embodiment, when the electric box wrench is operated, the support body 2 is pulled toward the head 16a via the nut member 18 screwed into the screw portion 16c, and the clamping surface 45 of the pad member 41 runs along the outer end surface p2 of the girder p1 on the side of the pallet P, and comes into contact with the entire surface.

[0047] When the electric box wrench is further operated from this state, the support body 2 is pulled further toward the head 16a, and the outer end surface p2 of the pallet P presses the pad member 40. If the pressing force F applied to the pad member 40 from the outer end surface p2 is a horizontal force passing through the pivot point Q2 for the pad arm 37, then the lower link arm 35 tries to rotate upward about the fulcrum S due to a component force F1 in a direction perpendicular to the line connecting the pivot point Q2 and the fulcrum S at the lower end of the lower link arm 35 at the pivot point Q2.

[0048] The pad member 41 is pivoted at the pivot point Q2 so as to be able to swing up and down, so that it swings in accordance with the upward rotation, and the entire surface of the pad 43 comes into contact with the outer end surface p2 of the pallet P.

[0049] Then, when the lower link arm 35 attempts to rotate around the fulcrum S in the direction in which the pad member 41 rises, as in the first embodiment, the lower link arm 35 rotates in the direction in which the pad member 41 is lifted around the bolt of the base pivot hole 23b (lower link pivot hole 35a), which serves as the point of action K.

[0050] The pad members 41 are provided on both ends 3 and 13 of the pallet support member 1 and abut against both outer end faces p2 of the girder p1 on one side of the pallet P, so that when the head 16a of the screw member 16 of this pallet lift B is operated, both pad members 41 rotate in the upward direction at the same time, lifting up the girder p1 on one side of the pallet P. At this time, the entire surface of the rubber pad 43 is in contact with the outer end face p2 of the pallet P, so the outer end face p2 of the pallet P can be lifted without being damaged. When the pallet lift B is raised to a specified height, the electric box wrench is stopped and removed from the head 16a. When the electric box wrench is removed, the weight of the load N and pallet P is applied to the pad member 41, which tries to push the pad member 41 downward, but as in the first embodiment, the center of rotation of the pad member 41 is fixed at the stepped lower pin 70 (fulcrum S) at this point and does not expand forward or backward, so the pad arm 37 is biased in a direction to push the pad member 41 into the outer end face p2 of the girder p1 on the side of the pallet P. As a result, the pad members 41 on both ends of the pallet support member 1 clamp both outer end faces p2 of the girder p1 on the side of the pallet P from both sides, so the pallet P does not slip down.

[0051] When the lifting operation of one pallet lift B is completed, the same operation is performed to lift the girder p1 on the opposite side of the pallet P. When the lifting of the pallet P is completed, the pallet P is pulled (or pushed) and moved, and removed at the destination.

[0052] A third embodiment of the present invention will now be described. As shown in Figures 12 to 14, a pallet lift C of the third embodiment is attached to the four corners of a pallet P when in use. Structurally, it has the same structure as the first embodiment, using cam members 40, caster members 20, and parallel link members 30 on the slide member 12 side, but is different in that a fixed clamp receiving member 50 is used on the end portion 3 side of the support body 2.

[0053] The pallet P to which the pallet lift C of the third embodiment is applied is of the four-way insertion type with blocks p4 formed of square timber at the four corners as shown in Figure 19. The pallet support member 1 is short in length to match this block p4. The mechanism portion having the cam member 40 pivotally attached to the slide member 12 side of the pallet support member 1 is the same as that of the first embodiment as described above. The end portion 3 side of the support portion main body 2 is equipped with a fixed clamping member 50. The fixed clamping member 50 is fixed to the end portion 3 via a spacer 58 by means of a bolt.

[0054] The clamping surface 55 of the clamping receiving member 50, which abuts against the inner end face p6 of the block p4, is formed in a convex arc shape and abuts against the inner end face p6 at one point. The surface of the clamping surface 55 has a large number of triangular projections and recesses with grooves engraved in the width direction, similar to the cam member 40. The abutment point Q3 of the clamping surface 55 with respect to the inner end face p6 is higher than the abutment point Q1 with respect to the end face p5 of the cam member 40.

[0055] Then, as shown in FIG. 14, the pallet lift C is placed at one corner of the pallet P, and the screw member 16 is operated to clamp the outer and inner end faces p5 and p6 of the block p4. When the electric box wrench is further operated from this state, similarly to the first embodiment, the support body 2 is further drawn toward the head 16a, and the cam member 40 rotates in the rising direction.

[0056] The cam member 40 and the clamping member 50 abut against the outer and inner end faces p5 and p6 of the block p4 at points Q1 and Q3, clamping the block p4. When the cam member 40 rotates in the lifting direction, the cam member 40 meshing with the outer end face p5 of the block p4 lifts the block p4 by the parallel lifting action of the parallel link member 30 shown in the first embodiment. However, at this point, the pallet P tilts because the pallet lift C is only attached to one corner. Although not shown, the contact point Q1 is raised to approximately the same height as the contact point Q3.

[0057] By performing the above operation at the four corners of the pallet P, the pallet P can be lifted horizontally. Once the lifting of the pallet P is complete, the pallet P is pulled (or pushed) and moved, and then removed at the destination. Although a cam-shaped member is used as the clamping receiving member 50, a ring-shaped member that rotates by a ring surface abutting against the inner end face p6 may be used instead.

[0058] A fourth embodiment of the present invention will now be described. As in the third embodiment, the pallet lift D of the fourth embodiment is attached to the four corners of a pallet P as shown in Fig. 12 when used. Structurally, it is the same as the second embodiment in which a pad member 41 is used on the slide member 12 side, and has the same structure using the pad member 41, caster member 20, and parallel link member 30. In the fourth embodiment, the fixed side clamping member 51 is also of the pad type. The fixed side clamping member 51 has the same structure as the pad member 41 on the sliding member 12 side, and is composed of a pad mounting portion 52 and a pad 53. The pad mounting portion 52 is composed of a pad mounting surface member 52a and a pair of pivotal mounting plates 52b provided perpendicularly thereto, and the pivotal mounting plates 52b are provided with mounting holes 52h.

[0059] The pad 53 is made of, for example, a hard rubber plate and is attached to the pad mounting surface material 52a. The pad mounting portion 52 is fixed to the end portion 3 of the support body 2 via a spacer 58 by a bolt inserted into the mounting hole 52h. The entire surface of the pad 53 of the pad-type holding member 51 abuts against the inner end surface p6 of the block p4. The mounting hole 52h of the pad-type holding member 51 is located above the force point Q2 of the pad member 41 on the slide member 12 side.

[0060] Then, as shown in FIG. 12, the pallet lift D is placed at one corner of the pallet P, and the screw member 16 is operated to clamp the outer and inner end faces p5 and p6 of the block p4. When the electric box wrench is further operated from this state, as in the second embodiment, the support body 2 is further pulled toward the head 16a, and the clamping surface 45 of the pad member 41 and the clamping surface 55 of the pad-shaped clamping receiving member 51 come into contact with the outer and inner end faces p5 and p6 of the block p4 of the pallet P.

[0061] When the electric box wrench is further operated from this state, the support body 2 is pulled further toward the head 16a, the outer end face p2 of the pallet P presses against the pad member 41, and, as in the second embodiment, the lower link arm 35 rotates upward about its fulcrum S, lifting up the block p4 at one corner with the block p4 sandwiched between the pad-shaped clamping receiving member 51 and the pad member 41.

[0062] When only one corner block p4 is lifted, the pallet P tilts, but the pad-type clamping receiving member 51 and the pad member 41 swing up and down in accordance with this tilt, and the pads 43, 53 remain clamped by the block p4 and do not shift.

[0063] Once the lifting operation of the pallet lift D at one corner is completed, the same operation is performed at the remaining three corners to lift the pallet P horizontally. Once the lifting of the pallet P is completed, the pallet P is pulled (or pushed) and moved. Although not shown, the clamping members 50 and 51 in the third and fourth embodiments may be replaced by a one-way bearing that rotates upward but does not rotate downward, attached to a spacer 58 provided at the end 3 of the support main body 2, so that the clamping members 50 and 51 rotate while coming into contact with the inner end surface p6 of the block p4 of the pallet P when lifted. [Explanation of symbols]

[0064] A~D: pallet lift, F: pushing force, F1: force component, G: floor surface, K: point of action, L1·L2: distance, N: cargo, P: pallet, p1: side girder, p2: outer end face, p20: inner girder, p30: edge board, p31: deck board, p4: blocks at the four corners, p40: inner block, p5: outer end face of block, p6: inner end face of block, Q1: contact point, Q2: pivot point for pad arm, Q3: contact point for inner end face, R·R1·R2: radius, S: pivot point (fulcrum) 1: pallet support member, 2: support body, 3: outer end of support body, 4a: upper pivot hole on body side, 4b: lower pivot hole on body side, 5: insertion side end, 6: round hole, 12: slide member, 12a: insertable / detachable member body, 12b: screw fixing plate, 13: outer end of slide member, 14: holding block, 14U and 14D: upper and lower blocks, 14a and 14b: upper and lower pivot holes, 14h: rotation holding hole, 15: telescopic drive member, 16: screw member, 1 6a: head, 16b: neck, 16c: screw portion, 16d: screw receiving member, 18: nut member, 19: square tube member, 19a: upper pivot hole, 19b: lower pivot hole, 20: caster member, 21: base, 22: horizontal plate, 23: vertical plate, 23a-23b: base side pivot hole, 29: running wheel, 30: parallel link member, 31: (upper) link arm, 31a: upper link first pivot hole, 31b: upper link second pivot hole, 31c: upper link intermediate round hole, 35: (lower) link arm, 35a: lower link first pivot hole, 35b: lower link second pivot hole, 35c: lower link intermediate round hole, 37: pad arm, 37a: pad pivot hole, 40: cam member, 40b: fulcrum hole, 40c: fixing round hole, 41: pad member, 42: pad mounting portion, 42a: pad mounting surface material, 42b: pivot plate material, 42h: mounting hole, 43: pad, 45: clamping surface, 50: clamp receiving member, 51: clamp receiving member, 5 2: pad mounting portion, 52a: pad mounting surface material, 52b: pivot plate material, 52h: mounting hole, 53: pad, 55: clamping surface, 58: spacer, 60: stepped upper pin, 61: wide wide diameter portion, 63: link side shaft portion, 65: member side shaft portion, 68: spacer ring, 70: stepped lower pin, 71: narrow wide diameter portion, 73: link side shaft portion, 75: member side shaft portion, 100: conventional pallet lift for pallets, 110: pallet support member, 120: roller

Claims

1. A pallet support member including a support body arranged along a side beam of the pallet and a slide member arranged to be inserted and removed horizontally relative to the support body; an expansion and contraction driving member attached to the slide member and configured to move the support body in an insertion and removal direction; Caster members each provided adjacent to both ends of the pallet support member and each having a running wheel; Parallel link members that connect the ends of the pallet support members to the caster members and raise and lower the pallet support members relative to the caster members; a cam member attached to any one of the link arms of the parallel link member and having a clamping surface that comes into contact with and separates from the outer end surface of the beam on the side surface of the pallet, A pallet lift characterized in that the lower end of the link arm to which the cam member is attached is pivotally attached to each end of the pallet support member so as to be rotatable in the vertical direction, and the pivotal attachment portion of the link arm is formed so as to be positioned below the abutment point of the cam member against the outer end surface of the girder on the side of the pallet.

2. A pallet support member including a support body arranged along a side beam of the pallet and a slide member arranged to be inserted and removed horizontally relative to the support body; an expansion and contraction driving member attached to the slide member and configured to move the support body in an insertion and removal direction; Caster members each provided adjacent to both ends of the pallet support member and each having a running wheel; Parallel link members that connect the ends of the pallet support members to the caster members and raise and lower the pallet support members relative to the caster members; a pad member attached to any one of the link arms of the parallel link member and having a clamping surface whose entire surface comes into contact with and separates from the outer end surface of the side beam of the pallet; the link arm to which the pad member is attached includes a pad arm extending obliquely upward from the end portion on the pallet support member side toward the outer end face of the girder on the side surface of the pallet, the pad arm includes a pad pivot hole for pivotally mounting the pad member so as to be vertically swivellable; A pallet lift characterized in that the extended portion of the pad arm of the link arm is pivotally attached to each end of the pallet support member so as to be rotatable in the vertical direction, and the pivot portion of the link arm is formed so as to be positioned below the pad pivot hole of the pad arm.

3. A pallet support member including a support body arranged along the outer surface of a block provided at each of the four corners of the pallet, and a slide member provided so as to be inserted and removed horizontally relative to the support body; an expansion and contraction driving member attached to the slide member and configured to move the support body in an insertion and removal direction; A caster member provided adjacent to an end of the slide member located outside the block of the pallet and having a running wheel; A parallel link member that connects the end of the slide member and the caster member and raises and lowers the pallet support member in the vertical direction relative to the caster member; A link arm of the parallel link member is attached to the outside of the block of the pallet. A cam member having a clamping surface that comes into contact with and separates from an end surface of the cam member; a clamping member that is attached to the support body, that comes into contact with and separates from an inner end surface of the block opposite to an outer end surface of the block on the cam member side, and that clamps both inner and outer end surfaces of the block between the block and the cam member; A pallet lift characterized in that the lower end of the link arm to which the cam member is attached is pivotally attached to each end of the pallet support member so as to be rotatable in the vertical direction, and the pivotal attachment portion of the link arm is formed so as to be positioned below the abutment point of the cam member against the outer end surface of the girder on the side of the pallet.

4. A pallet support member including a support body arranged along the outer surface of a block provided at each of the four corners of the pallet, and a slide member provided so as to be inserted and removed horizontally relative to the support body; an expansion and contraction driving member attached to the slide member and configured to move the support body in an insertion and removal direction; A caster member provided adjacent to an end portion of the slide member located outside the block and having a running wheel; a parallel link member that connects the end portion located outside the block to the caster member and raises and lowers the pallet support member in the vertical direction relative to the caster member; a pad member attached to any one of the link arms of the parallel link member and having a clamping surface whose entire surface comes into contact with and separates from an outer end surface of the block of the pallet; a clamping member attached to the support body, the entire surface of which comes into contact with and separates from an inner end surface of the block located opposite the outer end surface, and which clamps both inner and outer end surfaces of the block between the pad member and the clamping member, the link arm to which the pad member is attached includes a pad arm extending obliquely upward from the end portion on the slide member side toward the outer end face of the block of the pallet, the pad arm includes a pad pivot hole for pivotally mounting the pad member so as to be vertically swivellable; A pallet lift characterized in that the portion of the link arm from which the pad arm is extended is pivotally attached to the end of the slide member so as to be rotatable in the vertical direction, and the pivot portion of the link arm is formed so as to be positioned below the pad pivot hole of the pad arm.

5. The pallet lift according to any one of claims 1 to 4, characterized in that the telescopic drive member is composed of a rotatable screw member arranged horizontally on the slide member, and a nut member screwed onto the screw member so as to be freely threaded forward and backward and attached to the support body.

6. 4. A pallet lift according to claim 3, wherein the clamping surface of the clamping member is formed in a convex arc shape so as to make point contact with the end face of the clamping member.

7. A pallet lift as described in claim 4, characterized in that the clamping receiving member is pivotally attached to a spacer attached to the support body so as to be able to swing up and down, and is provided with a receiving pad member the entire surface of which contacts the inner end surface of the block.

Images