JP3380174B2 - Side fork type transfer vehicle - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a side fork type transfer vehicle used for, for example, an automated transfer line. 2. Description of the Related Art Conventionally, as this type of side fork-type transfer vehicle, for example, the structure shown in FIGS. 3 to 5 has been provided. That is, the vehicle body 1 is capable of traveling on the floor via the front wheel 2 and the rear wheel 3, and at that time, the traveling is performed by a pickup coil provided on the front wheel 2 or the rear wheel 3 transmitting electromagnetic waves on an induction wire on the floor side. By catching, it is performed on a certain route. And, at a plurality of lower portions of the vehicle body 1, there are provided outriggers 4 for preventing overturning which can freely contact and separate from the floor, and these outriggers 4 are of a cylinder type. A pair of left and right guide rails 5 are provided on the vehicle body 1 between the front and rear, and a movable body 6 is provided between the guide rails 5. 7 is erected. The movable body 6 and the mast 7
A pair of left and right guide rollers 8 are provided before and after, respectively. The guide rollers 8 are fitted and guided on the guide rails 5 so that the movable body 6 and the mast 7 can reciprocate in the left and right directions. Be composed. An elevating body 9 guided by both masts 7 is provided, and the elevating body 9 is provided with a fork 10 facing in the left-right direction. The elevating body 9 is
It is moved up and down by a lift cylinder 11. [0004] A reach device 41 is provided for protruding the fork 10 in the left-right direction. The reach device 41 is of a link type, and includes a gantry 42 provided on the vehicle body 1 side, a fixed-side link 43 provided on the gantry 42 to be rotatable left and right, and A movable link 44 provided, a connecting pin 45 in the front-rear direction for connecting the free ends of both links 43 and 44 so as to be relatively rotatable,
It is composed of an operating cylinder 46 connected to the connecting pin 45 and the like. [0005] According to such a conventional configuration, as shown by the phantom line in FIG.
Is contracted, and the links 43 and 44 are relatively opened, whereby the movable body 6 and the mast 7 are laterally moved via the guide rollers 8, whereby the fork 10 can be protruded in the lateral direction. Further, as shown by the solid line in FIG. 3, the movable cylinder 6 is extended and the two links 43 and 44 are relatively closed to move the movable body 6 and the mast 7 in the opposite direction via the guide rollers 8. Moved, fork 10
Can be withdrawn. By appropriately incorporating the elevating movement of the elevating body 9 by the lift cylinder 11, that is, the elevating movement of the fork 10, loading and unloading of the intended conveyed object can be performed. [0006] According to the above-described conventional configuration, since the load of a conveyed object or the like is received only by the guide rollers 8, the guide roller pitch L is set large.
Although the load applied to the guide roller 8 is limited, in this case, the larger the guide roller pitch L, the larger (wider) the vehicle body width R. In order to reduce (narrow) the vehicle body width R and provide sufficient load support, it is conceivable to increase the diameter of the guide roller 8. However, in this case, the cost of the guide rail 5 and the guide roller 8 increases significantly. Become. SUMMARY OF THE INVENTION It is an object of the present invention to provide a side fork type transfer vehicle which can minimize the guide roller pitch and can use a small (small diameter) guide roller. Things. In order to achieve the above object, a side fork-type transfer vehicle according to a first aspect of the present invention is provided with a left-right guide rail on a vehicle body. A side-fork type transfer in which a mast that is reciprocally movable in the left-right direction is provided by being supported and guided on a guide rail via a plurality of left and right guide rollers, and a fork that is moved up and down by a lift cylinder is provided on the mast side. A reach device for moving the fork in the left and right direction, the reach device is a chain drive type, and one end of the chain is connected to the mast side via a tension cylinder, and the lift It is characterized in that the pressure of the cylinder is transmitted to the chain via the tension cylinder. Therefore, according to the first aspect of the present invention, the mast is laterally moved in the left-right direction via the guide rollers by driving the reach device in the normal and reverse directions and moving the chain in the normal and reverse directions. Can be moved in and out. Then, by appropriately incorporating the lifting and lowering movement of the fork by the lift cylinder, it is possible to load and unload the intended goods. When performing such an operation, the pressure of the lift cylinder is transmitted to the chain via the tension cylinder, and the pressure is applied to one end of the chain as tension. The load can be reduced. Embodiments of the present invention will be described below.
A description will be given based on FIGS. Note that the same or substantially the same components as those in the related art (FIGS. 3 to 5) are denoted by the same reference numerals, and the details are omitted. That is, 1 is the body, 2
Is a front wheel, 3 is a rear wheel, 5 is a guide rail, 6 is a movable body, 7
Denotes a mast, 8 denotes a guide roller, 9 denotes an elevating body, 10 denotes a fork, and 11 denotes a lift cylinder. A reach device 20 for moving the fork 10 in the left-right direction is divided into a pair of frame bodies 12 erected from the front and rear sides of the vehicle body 1 and provided in a pair of front and rear sides. That is, each reach device 20 is of a chain drive type and has four (plural) sprockets 21, 22, 23,
24, of which the lower sprockets 21 and 22
Are provided at both ends in the left-right direction of the frame body 12, and one upper sprocket 23 is provided at an end of the frame body 12 opposite to the protruding side of the fork 10, and the other one sprocket at the upper part is provided. Reference numeral 24 is provided at an upper and lower middle position of the mast 7. A chain 25 is disposed between the sprockets 21 to 24. At this time, the chain 25 is hung from the lower side between the lower sprockets 21 and 22,
It is hung from the outside between the upper and lower sprockets 22 and 23, and hung from the upper side between the upper sprockets 23 and 24. The other end 25B of the chain 25 hung from below on the lower sprocket 21 is inverted to the upper side of the sprocket 21 and then connected to the lower part of the mast 7 (movable part side) via a connecting member 26. Have been. Further, the chain 2 has a different horizontal direction from the other end 25B of the chain 25 with respect to the mast 7 side.
One end 25A of the mast 7 is hung from above on the sprocket 24 of the mast 7, is guided to a lower side of the sprocket 24, and is connected to the mast 7 side (movable portion side) via a tension cylinder 27. . That is, in the tension cylinder 27, the lower end of the cylinder main body 28 is connected to the mast 7, and the upper end of the upward piston rod 29 is connected to one end 25A of the chain 25. The frame 12 is provided with a rotation drive device 30 that is linked to the sprocket 22. The pressure of the lift cylinder 11 is transmitted to a chain 25 via a tension cylinder 27. That is, the drive side pump 3 is provided in the extension side oil supply / discharge passage 32 provided between the extension chamber 11 a of the lift cylinder 11 and the oil tank 31.
3, a relief valve 34, an electromagnetic switching valve 35 and the like are interposed. A contraction-side oil supply / discharge passage 36 is provided between the contraction chamber 11 b of the lift cylinder 11 and the oil tank 31. The extension-side oil supply / discharge passage 32 is connected to the contraction chamber 27b of the tension cylinder 27 via a contraction-side communication passage 37 between the electromagnetic switching valve 35 and the extension chamber 11a. The path 36 communicates with the extension chamber 27 a of the tension cylinder 27 via an extension communication path 38. The operation of the above embodiment will be described below. By driving the rotation drive device 30 of the reach device 20 in the normal and reverse directions and by rotating the sprocket 22 to move the chain 25 in the normal and reverse directions, the movable body 6 and the mast 7 are laterally moved in the left-right direction via the guide rollers 8. As a result, the fork 10 can be moved back and forth in the lateral direction. That is, for example, the movable body 6 and the mast 7 at the retreat position are moved from the solid line in FIG. 1 to the virtual line B in FIG. The fork 10 can be laterally moved in the lateral direction as shown in FIG. Also, the movable body 6 and the mast 7 in the protruding position as shown by the imaginary line B in FIG. 1 are moved in the left-right direction from the solid line in FIG. Lateral movement may cause the fork 10 to retreat laterally. Then, the lifting body 9 is moved up and down by the lift cylinder 11,
That is, by appropriately incorporating the lifting and lowering movement of the fork 10,
It is possible to load and unload the intended goods. In performing such an operation, by transmitting the pressure of the lift cylinder 11 to the chain 25 via the tension cylinder 27, the load applied to the guide roller 8 can be reduced even if the load on the fork side increases or decreases. That is, the pressure P applied to the extension chamber 11a of the lift cylinder 11 via the extension-side oil supply / discharge passage 32
Is connected to the tension cylinder 2 via the contraction side communication passage 37.
7, one end 25 of the chain 25 via the tension cylinder 27.
A will act as tension. At this time, when Wg: load E: load center distance F: tension force of the chain 25 S: pitch of the chain 25, the relationship between the pressure P of the lift cylinder 11 and the tension cylinder 27 is as follows. Wg × E = F × S (Equation I) where: Al: area of cylinder inner diameter of lift cylinder 11 At: surface of cylinder inner diameter of tension cylinder 27
Product P: Assuming that the pressure of the lift cylinder 11 is Wg = P × Al F = P × At, (Formula I) becomes At = Al × S / E (Formula II). At that time, the cylinder of the lift cylinder 11
The relationship between the area Al of the inner diameter and the area At of the cylinder inner diameter of the tension cylinder 27 only needs to satisfy (Expression II). Here, assuming that the load applied to the guide roller 8 is W and the guide roller pitch is 1, W × l = Wg × E−F × S W × l = (Wg × E−F × S) / l. ... (Formula III) According to the formula (I), since the numerator of the formula (III) is 、 0, the load W applied to the guide roller 8 is ≒ 0 and is not affected by the load Wg. As described above, the load W applied to the guide roller 8 can be reduced by properly combining the area Al of the inner diameter of the cylinder of the lift cylinder 11 and the area At of the inner diameter of the cylinder of the tension cylinder 27. And the guide roller pitch l can be reduced, and the vehicle width r can be reduced (narrowed). In the above-described embodiment, the arrangement of the chain 25 via the sprockets 21 to 24 is merely an example. For example, the sprockets 22 and 23 are arranged on the protruding side and are arranged in the opposite direction. The arrangement position and form can be arbitrarily changed. The reach device 20 of the above-described embodiment and the like can be incorporated in place of the reach device 41 of the side fork-type transfer vehicle having the above-described conventional configuration (FIGS. 3 to 5). A space is created inside the vehicle body, and the degree of freedom in arranging parts is created. According to the first aspect of the present invention, the pressure of the lift cylinder is transmitted to the chain via the tension cylinder, and the pressure is applied to one end of the chain as tension, so that the fork side is provided. Even if the load increases or decreases,
The load applied to the guide rollers can be reduced, the guide rollers and guide rails can be made smaller (smaller diameter), and the guide roller pitch can be made as small as possible. Can be performed at low cost.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an example of an embodiment of the present invention and is a longitudinal sectional front view of a side fork-type transfer vehicle. FIG. 2 is an operation explanatory view including a hydraulic circuit in the side fork type transfer vehicle. FIG. 3 is a longitudinal sectional front view of a side fork-type transfer vehicle, showing a conventional example. FIG. 4 is a partially cutaway side view of the side fork-type transfer vehicle. FIG. 5 is a partially cutaway plan view of the side fork-type transfer vehicle. [Description of Signs] 1 Body 5 Guide rail 6 Movable body 7 Mast 8 Guide roller 9 Elevating body 10 Fork 11 Lift cylinder 12 Frame 20 Reach device 21 Sprocket 22 Sprocket 23 Sprocket 24 Sprocket 25 Chain 25A One end 25B Other end 27 Tension cylinder Reference Signs List 30 rotation drive device 31 oil tank 32 extension-side supply / discharge oil passage 33 pump 36 contraction-side supply / discharge oil passage 37 contraction-side communication passage 38 extension-side communication passage

Claims (1)

(57) [Claims 1] A left and right guide rail is provided on a vehicle body, and the guide rail is supported and guided by a plurality of left and right guide rollers, so that it can reciprocate in the left and right direction. A side fork-type transfer vehicle provided with a fork that is moved up and down by a lift cylinder on the mast side, and a reach device that moves the fork in the left-right direction is provided. The reach device is a chain drive type, and one end of the chain is connected to the mast side through a tension cylinder, and the pressure of the lift cylinder is configured to be transmitted to the chain through a tension cylinder. Fork-type transfer vehicle.