FI123773B - Device for transferring a pallet and method for moving pallets and work unit - Google Patents

Description

PALLET TRANSFER EQUIPMENT AND METHOD FOR MOVING PALLETS AND WORKING CELL

OBJECT OF THE INVENTION 5

The invention relates to a pallet transfer apparatus for handling multiple pallets. The invention further relates to a method for moving a plurality of pallets and to a working cell comprising a pallet transfer apparatus and a machine tool.

10

Background of the Invention

Different pallets are used in connection with automatic machining and assembly equipment to transfer workpieces and / or machine tool tools. Different conveyors are used to move the pallets. US 4,326,624 discloses a pallet transfer apparatus capable of handling multiple pallets. The pallets are positioned horizontally on the circumference of the pallet transfer equipment, where they can be rotated by rotating the equipment body. The pallets are transferred from the periphery of the apparatus to, for example, a machine tool using a linear motion tool.

BRIEF SUMMARY OF THE INVENTION A solution has now been found which enables a simpler design of a pallet transfer apparatus.

o

C \ J

In order to accomplish this purpose, the pallet transfer apparatus according to the invention is essentially characterized by what is stated in the independent claim 1. The method according to the invention, in turn, is essentially characterized by what is disclosed in the independent claim.

In particular, the working cell according to the invention is essentially characterized by what is disclosed in independent claim 10. Other dependent claims 35 disclose some preferred embodiments of the invention.

2

The basic idea of the invention is to place the pallets on the fastening members, and the fastening member is moved in a first direction about an axis by rotating the conveyor body in a first direction, and the moving member is moved in moving in the other direction by rotating the body in the opposite direction to the first direction. In one embodiment, the fastening members are moved by arms connected to the frame and the fastening member, and the movement of the fastening member 10 is defined by a circumferential path and one or more lateral paths which deviate from the direction of the circumferential path.

The pallet transfer apparatus according to the invention comprises means for moving the pallet about an axis and means for moving the pallet at least two to 15 different distances from the axis. The means comprise a body adapted to rotate about an axis in a first direction and a second direction, and a fastening member on which the pallet can be placed. Further, the means comprise a shaft disposed between the body and the fastening member, the arm being adapted to move the fastening member about the axis when the body 20 rotates in the first direction, and the arm adapted to move the fastening member at a second distance from the shaft. In a preferred embodiment, the means further comprises a web adapted to guide the attachment member, which orbits the axis, and further comprises at least one sidewall, and the arm is adapted to pull the attachment member along a path defined by the web. clockwise), and the arm ™ is adapted to push the retaining member along a path defined by the side track as the body rotates in another direction (e.g., counterclockwise).

't C \] * 30 In one embodiment, there are at least two sidewalls, the first of which is for guiding the fastening member to the machine tool and providing - [{? this side track is for guiding the mounting member to the charging station.

LO

O)

O

S In one embodiment, the web comprises an aperture from which the mounting member can be pivoted off the web.

3

In one embodiment of the invention, the track and side track interface has a control device. In a preferred embodiment, the control device is spring-loaded. In another embodiment, the control device is provided with an actuator for changing the position of the control device.

5

The various embodiments of the present solution, individually and in combination, offer different advantages. Following are some of the benefits that one or more applications may have depending on its implementation.

10 - Only one actuator for pallet movement - Can be transported in one piece for easy installation - Simple control of pallet transfer equipment - Mechanically strong structure - High speed of operation 15 - Variable side rails - Easy modulation

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail with reference to the accompanying principal drawings, in which Fig. 1 is a perspective view of an automatic machining system in a perspective view of 25 "Fig. 2 in another direction.

O

C \ J

Figure 3 shows the first situation seen from above

C \ J

x 30 Figure 4 shows another situation seen from above

CL

Fig. 5 shows a third view from above m σ> o Fig. 6 shows a third view in perspective view 35 Fig. 7 shows an embodiment of the control device 4

For the sake of clarity, the drawings show only the details necessary for an understanding of the invention. Unnecessary to the understanding of the invention but obvious to one skilled in the art, structures and details have been omitted in order to emphasize features of the invention.

Detailed Description of the Invention

Figures 1 and 2 show, in principle, a working cell of an automatic machining system 10. In the example, the machining system comprises a machine tool 1 and a pallet transfer device 2. The machining systems may further comprise other components such as loading stations, robots, tool magazines, pallet magazines and pallet paths. The figures show a loading and processing station which enables manual operation. In addition, the figures show pieces 3 placed on top of the pallet.

The exemplary pallet transfer apparatus 2 comprises means for simultaneously handling four pallets of 20 pallets, but other means may be provided. These means comprise e.g. arms 4 and supports 5, such as can be seen in Figure 6. A plurality of arms 4 are connected to one common body 6, preferably by a pivoting structure 7, which allows horizontal pivoting and substantially prevents vertical movement. The body 6 is preferably arranged to be rotatably horizontal. The body 6 then rotates about the vertical axis 8 ™. The supports 5 and the pallets on top of them are supported by the arms 4. Advantageously, the supports 5 are also pivotally connected to the arms 4 so that the structure allows horizontal rotation and prevents substantially vertical movement. It is also possible to implement the structure in such a way that there is no separate substrate 5 but a pallet switch

Other suitable fastening means sits directly on the arm, m σ> o ° Preferably, the length of the arm 4 is greater than the distance of the pivot point 7 from the circumference 35 (i.e. the circumferential track 9 described below). The other end of the arm 4 is then located outside the periphery 9 when the arm is guided to the side track 10 as described later in this specification.

The rotary body 6 is in turn connected to a stationary stand 11.

5 A guide track 9 is formed on the base 11, and the arms are guided on a guide track. In the example, the track 9 is used as a track, but the deflection movement can be accomplished in a variety of ways, such as a toothed rack, toothed ring, or chain / sprocket. These other alternative solutions for deflection movement are not specifically described herein, but the most preferred solution is used as an example.

In the exemplary embodiment, the guide track comprises a circular portion 9 and a side track 10 for a machine tool. The track 9 may also have a closed loop shape other than a circle, such as an oval, of some other shape. In addition, the track 9 may have a side track 10 to a charging station or other operating point. The palettes remain on the circular track 9 when rotated in the first direction, i.e. clockwise in the example. When rotated in the opposite direction (counterclockwise), the pallet 20 is guided to the side track 10. Figs. Fig. 3 is a top plan view showing the pallets located on the circular track 9 and the arms 4 in the first extreme positions. Fig. 4, in turn, has a pallet on the sidewall 10 leading to the machine tool 1, with the arm 4 associated with said securing member 5 being between the first and second "extreme" positions. In Figures 5 and 6, the pallet is shifted to machine tool 1,

O

™ with arm 4 extended to the other end position.

CD

cp S Preferably, the movements of the pallet transfer apparatus 2 are achieved by a single actuator (not shown), preferably by an electric motor having two directions of rotation. The actuator rotates the body 6 in two directions £ (clockwise and counterclockwise). Preferably, the direction of rotation of the electric motor § is changed by changing the connections. The actuator may also be another type of motor dj and the change of direction may be effected in various ways, for example by a transmission.

6

Advantageously there are guide means 12 at the intersections of the track 9, such as spring-loaded tongues. Figure 7 shows a detail of an embodiment of the guide device 12 in which the tongue closes the passage of the track 9. As the frame 6 is rotated in the first direction, the tongue 12 which closes the rail 5 9 opens each time the fastening member 5 passes by.

When rotated in the other direction (i.e. feed direction), the tongue 12 closing the rail 9 turns the fastener 5 to the sidewall 10. Fig. 7 shows the fastener 5 and the pallet thereon by the sidewall 10. The tongues 12 or other control devices can also be controlled by an actuator. Here, it is possible to select me-10 whether the fastening elements 5 and the pallets attached to them are simultaneously or separately, for example, for the machine tool 1 and the loading station if the pallet transfer device 2 comprises sidewalls 9 for these work stations.

If no separate loading station is used in the pallet transfer apparatus 2, the track 15 may have a point from which the arm 4 can be freely pivoted about its pivot point 7. In one embodiment, the track 10 comprises an opening through which the fastening member 5 can be pivoted outside the track 9. The user then has access to at least three sides of the fastening member 5 and the pallet thereon.

20

In the preferred pallet transfer apparatus 2, pallets are not moved vertically by the pallet transfer apparatus. Preferably, the pallet changer of the machine tool 1 lifts the pallet off the shaft 4.

In the example described above, the first direction of rotation of the body 6 is clockwise and the second direction of rotation is anticlockwise. It is also possible to implement the apparatus such that the first rotation 9 of the body 6 is anticlockwise and the second rotation 9 is clockwise.

Further, the exemplary pallet transfer apparatus 2 comprises means for simultaneously processing four pallets. The means may also be of different amounts of r £, such as one, two or more, whereby one, two or more pallets may be processed simultaneously. Preferably, the S pallet transfer apparatus 2 has means for processing 3-6 pallets.

35 7

By combining the operating modes and structures presented in connection with the various embodiments of the invention described above in different ways, various embodiments of the invention may be obtained which are in accordance with the spirit of the invention. Therefore, the foregoing examples should not be construed as limiting the invention, but embodiments of the invention may freely vary within the scope of the inventive features set forth in the claims below.

C/O

δ c \ j i

CD

O

C \ l

X

cc

CL

1 ^ m m O) o o

CM

Claims (12)

A pallet transfer apparatus comprising means for moving one or more pallets about an axis and means for moving the pallet at least two different distances from the axis, the means comprising - a frame (6) adapted to rotate about the axis (8) in a first direction and a second direction , - a fastening member (5) on which the pallet can be placed, characterized in that the means further comprise a 10. arm (4) between the body (6) and the fastening member (5), the arm being adapted to move the fastening member to the shaft (8). around the frame rotating in the first direction, and the arm adapted to move the securing member at a second distance from the axis when the frame rotates in the other direction. 15 Pallet transfer device according to claim 1, characterized in that the means further comprise a web (9) arranged to guide the fastening member (5), which web rotates the shaft (8) at a first distance and further comprises at least one side web (10) which guides a second distance from the shaft, and the arm is adapted to pull the fastening member along a path defined by the web (10) at a first distance from the shaft (8) as the frame rotates in a first direction; when the frame rotates in the other direction. 25 Pallet transfer device according to Claim 2, characterized in that there are at least two side tracks (10), the first side track being 0 for guiding the fastening element (5) to the machine tool (1) and the second side track being S for guiding the fastening element to the loading station. 1 30 Pallet transfer device according to claim 2 or 3, characterized in that the track (9) comprises an opening from which the fastening element (5) can be pivoted off the track. o C \ J Pallet transfer device according to one of the preceding claims 1 to 4, characterized in that a guide device (12) is provided at the interface between the track and the side track. Pallet transfer device according to claim 5, characterized in that the control device (12) is spring loaded. Pallet transfer device according to Claim 5, characterized in that the control device (12) is provided with an actuator for changing the position of the control device 10. A method for moving one or more pallets, the method of moving the pallet over a securing member (5) and moving the securing member in a first direction about an axis by rotating the body (6) of the transfer device (2) in a first direction; differs from the first direction in that the distance of the fastening member from the axis changes when moving in the second direction, characterized in that the fastening member (5) is moved in the second direction by rotating the body (6) in the opposite direction to the first direction. Method according to Claim 9, characterized in that the fastening element (5) is moved by a shaft (4) connected to the frame (6) and the fastening element and the movement of the fastening element is defined by a circumferential track (9) 25 and one or more lateral tracks (10) diverges from the track. o CvJ A work cell, comprising a machine tool (1) for processing pallets movable on pallets and a pallet transfer apparatus (2) for transferring pallets to a machine tool, and a pallet transfer apparatus for the working cell comprising means for moving at least one pallet about an axis (8) at two different distances from the axis, the means comprising: - a frame (6) adapted to rotate about the axis (8) in a first direction and a second direction, - a fastening element (5) on which the pallet can be placed, characterized by that the means further comprise: - a shaft (4) between the body (6) and the fastening member (5), the arm adapted to move the fastening member about the shaft (8) when the body rotates in the first direction, and the arm adapted distance from the axis when the frame rotates in the other direction. 11. A working cell according to claim 10, characterized in that the means further comprise a web (9) adapted to guide the attachment member (5), which orbits the shaft (8) at a substantially first distance and further comprises at least one sidewall (10). 10) leading to a second distance from the shaft and leading to a machine tool (1), the arm being adapted to pull the fastening member along a path defined by the web (9) at a first distance from the shaft (8) as the body rotates 15 in the first direction; along a path defined by the side track (10) for one distance from the axis when the frame rotates in the other direction. The working cell according to claim 11, characterized in that there are at least two sideways webs (10), the first sidewall being for guiding the fastening member (5) to the machine tool (1) and the second sidewalk being for guiding the fastening member to the loading station. CO δ (M CD cp 't CNJ X cc CL 1 ^ m m O) o o c \ j