JPS6054204B2 - Pallet intermittent transfer device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for intermittently transporting pallets on which various articles are placed.

Conventionally, a device that intermittently transports a pallet by providing a roller on the lower surface of the pallet and engaging the roller with a cylindrical cam having a rotation axis parallel to the direction in which the pallet travels has a guide rail (see Fig. 1). At least two rollers 2, 3 are provided on the lower surface of each of a plurality of pallets 1 which can be moved on (not shown), and a cylindrical cam 5 having a rotation axis 4 parallel to the guide rail is provided, The rollers 2 and 3 are engaged with the cam surface of the cylindrical cam 5 for positioning, and at least one pallet 1 is transferred, and the other pallets are placed in contact with the pallet that is engaged with the cylindrical cam 5. The intermittent pallet transfer device constructed in this way was constructed by providing a plurality of cylindrical cams 5, 5' along the guide rails so that the pallets could be transferred on the guide rails by touching each other.

However, in such a device, as shown in FIG. 2, which is a developed view of the cylindrical cams 5 and 5', two or more rollers (two in this example) on the lower surface of the pallet 1 are used to roll the cylindrical cams 5 and 5'. ,
5', or at least two
The pallet 1
, 1' are positioned and transferred intermittently, so when an appropriate gap is provided between the pallets in consideration of pallet processing errors, dust adhesion between pallets, and elongation due to temperature rise of the pallets, the cylindrical cam Only pallets 1 and 1' that engage with pallets 5 and 5' are accurately positioned, but many other pallets between them are not. The effect of clamping the protrusions is small. In addition, machining errors of pallets, dust adhesion between pallets, and temperature rise of pallets'
When the gap between the pallets is small, it is possible to set the gap between the pallets to zero or a negative value and apply preload between the pallets. However, what is effectively working during this preload between the pallets is the roller 3, the cam surface 8, and the roller 2'. Only the cam surface 7' and the provision of two rollers under each pallet are not effective. When we analyze the force that acts between the roller and the cylindrical cam during pallet transfer, we find that when the force between the pallet and the guide rail is ignored, the cam curve of a general intermittent transfer device as shown in Figure 5 shows that , when the pallet is transferred intermittently, the force is applied between the roller and the cam protrusion as shown by the arrow in Figure 3 in the positive acceleration section (in this example, between 0 and 60). It is divided into pressure A, pressurizing force B between a pallets, and c which accelerates the bl pallet group.

In the area where the acceleration is negative (in this example, between 60 and 120 degrees), the force is the pressing force A between the roller and the cam protrusion, and the pressure force A between the pallet, as shown by the arrow in Fig. 4. Pressure force B
, bl, a force d that decelerates the pallet group. Even when transferring pallets, the pressurizing force a between the roller and the cam protrusion is effective for accurately transferring only the pallet that engages with the cylindrical cam, but is not effective for transferring other pallets. . In addition, this pressing force a is useful for smooth rotation of the roller, but it is extremely difficult to apply a shimmy so that a constant pressing force a is applied in the transfer section due to the machining accuracy of the pallet, roller, and cam. , impractical. Furthermore, what is directly necessary for accurately transporting a group of pallets is the opposing cam surfaces 8, 7'' of the plurality of cylindrical cams and the roller 3 in contact therewith, as is clear from the explanation of FIGS. 3 and 4. 2'', and it is not effective to provide two or more rollers on the underside of each pallet to hold the protrusions of the cylindrical cam. In addition, although cylindrical cams are inherently expensive, it is possible to finish both sides of the protrusion of the cylindrical cam (or both sides of the cam groove) to the correct cam surface, and to machine the spacing with high accuracy. More than twice as much processing as finishing a chisel accurately! It costs money.
Moreover, since multiple such expensive cylindrical cams (usually 4 or more) are required, a large number of rollers are required, and the cost of drilling holes in the pallet increases. It is not economical to construct an intermittent pallet transfer device by providing more than one roller to clamp the protrusion of a cylindrical cam. By providing one roller on the underside of each pallet that engages with a cylindrical cam, the present invention provides at least two rollers under each pallet.
The object of the present invention is to provide an intermittent pallet transfer device that is comparable in performance and much more economical than a similar device that requires four individual rollers.

An embodiment of the present invention will be described below based on FIGS. 5 to 13.

11, 11 has one roller 12 on each lower surface thereof,
12'' and is slidably held on guide rails 13.

14 is a rotating shaft parallel to the guide rail 13, and 15 and 15'' are cylindrical cams having cam surfaces that engage with the rollers 12 and 125.

Between the pallet 11 and the pallet 1'' there is a pallet of the same shape that is transferred in contact with these pallets.The cylindrical cams 15, 15'' have a circle around their outer periphery as shown in the cam exploded view in Fig. 7). Projections 16, 16 slightly exceeded
'', and each of its opposing surfaces 17, 17''
is a cam surface that engages with the rollers 12, 12'', and its cam curve is perpendicular to the rotating shaft 14 in the pallet stopping section (120 mm to 360 mm in this example) and perpendicular to the rotating shaft 14 in the conveying section (in this example (between 00 and 120 axes), the rotation axis 14
The lead of the curve is equal to the pallet transport distance (usually the same as the pallet length).

The other surface 18,1'' of the protrusion 16,16'' remains as it was when the material of the cylindrical cam 15,15'' was cast. The entire apparatus for circulating pallets is as shown in Figure 8.
A right-handed helical cylindrical cam 15, 15'' on the rotating shaft 14 that transfers a group of pallets between pallets 11 to 1'' in the direction of arrow P.
The pallet transfer device of the present invention using
A pallet transfer device using a 5"
2, 12'' engages the cylindrical cams 25, 15, a pushing device (not shown), and when positioning the transfer device,
It is composed of a feed claw device (shown in the figure) that feeds the pallet group at positions I to 2 and the pallet group at positions C to 2 in the directions of arrows R1 and S, respectively, and as a whole counterclockwise in FIG. 8. Transfer pallets intermittently.

The rotating shafts 14, 24 are driven by a sprocket 31 on the output shaft of a reducer 30, which is driven by a motor 26 at the bottom of the device via a pulley 27, a belt 28, and a pulley 29, and a chain 32 and sprockets 33, 34. As a result, as shown in FIG. 10, it rotates counterclockwise at a constant speed.

The operation of positioning and feeding a pallet using this device will be explained.

In the cam positioning section (120 to 360 in this example), the opposing cam surfaces 17 and 1 are
The spacing r is kept constant, and the pallet group is kept in a fixed saw position by the rollers 12, 122 on the lower surfaces of the pallets 11, 112 at both ends coming into contact with the cam surfaces 17, 17'', respectively. At this time, if the distance between the cam surfaces 17 and 17'' is made smaller than the value at which the inter-pallet clearance becomes 0,
By applying a pressing force b between the pallets, high pallet stopping position accuracy can be obtained. In the pallet transfer section (in this example, between 00 and 120), the cam surfaces 17 and 17'' are curved inclined with respect to the rotation axis, and the contacting roller 1
The pallet group is sent in the advancing direction while keeping the distance between the centers of pallets 2 and 12' constant. The section in which the acceleration is positive among the transfer sections (
In this example, it is 0. ~60) Then, when Masatsu is ignored,
As shown in FIG. 12, a pressing force b and a force C that accelerates the pallet group act between the cam surface 17 and the roller 12.
Only the pressing force b acts between the cam surface 17'' and the roller 12''. The area where the acceleration is negative (600 to 1200 in this example)
In question), as shown in Fig. 13, a pressing force b acts between the cam surface 17'' and the roller 12, and a pressing force b acts between the cam surface 17'' and the roller 12'' to decelerate the pallet group. Therefore, even in the transfer section, the pallet group can be reliably restrained and transferred smoothly.In this embodiment, a cylindrical cam with one side of the protrusion as a cam surface is used. However, the same function and effect can be obtained by using a cylindrical cam with a cam groove bored on its outer circumference. By setting the number of turns to 2, 3, or 4, it is possible to easily manufacture a pallet intermittent device in which the transfer distance per rotation of the cylindrical cam is 112, 113, or 114 of the pallet length.

As described above, the present invention provides one roller on each lower surface of the pallet, and a plurality of cylindrical cams that engage with the rollers are provided along the guide rail of the pallet, and between the plurality of cylindrical cams. Since the pallet group is held by the rollers of the pallets at both ends and is transported while being positioned along the guide rail, this method requires at least two rollers under each pallet in the past. It has no inferiority in performance compared to an intermittent transfer device for pallets, and since only one cam surface of the cylindrical cam is required, the processing cost is low, the number of rollers is small, and the hole in the pallet is Processing costs are also low, and the apparatus as a whole is advantageous in that it can provide an economical and practical intermittent pallet transfer apparatus.

[Brief explanation of the drawing]

Figure 1 is a front view showing the main parts of a conventional intermittent pallet transfer device, Figure 2 is a developed view of the cylindrical cam used in the device, and Figures 3 and 4 are front views showing the operating principle of the device. Schematic,
FIG. 5 is a graph showing changes in acceleration of the cam curve used in the conventional device and an embodiment of the present invention, FIG. 6 is a front view of essential parts of an intermittent pallet transfer device in an embodiment of the present invention, and FIG.
The figure is a developed view of the cylindrical cam used in the device, Figure 8 is a plan view of the entire device, Figure 9 is its front view, and Figure 10 is the 9
A cross-sectional view taken along line X-X in the figure, Figures 11 and 12,
FIG. 13 is a front view of essential parts showing the operating principle of the device. 11,1"...Pallet, 12,12"...
... Mouth roller, 13 ... Guide rail, 14 ...
... Rotating shaft, 15,15" ... Cylindrical cam, 21,
2"... Pallet, 22, 22"... Roller, 23... Guide rail, 24... Rotating shaft, 25, 25"... Cylindrical cam.

Claims (1)

[Claims] 1 A roller is provided on the lower surface of each of a plurality of pallets that can be moved on guide rails, and a cylindrical cam having a rotating shaft parallel to the guide rail is guided so that the cam surface engages with the roller. A plurality of pallets are provided along the guide rail, and a group of pallets between the plurality of cylindrical cams is held by the cam surfaces of the plurality of cylindrical cams via rollers of pallets at both ends of the pallet group, and positioned along the guide rail. 1. A pallet intermittent transfer device, characterized in that the pallet is transferred intermittently.