JPH0761589B2 - A shuttle type pallet changing device that automatically captures and releases the pallet carrier at the standby position - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a manual shuttle type pallet changing device used for changing a work setting pallet in an automatic machine tool such as a machining center, and more particularly to pallet transfer. A manual shuttle-type pallet changer configured such that the platform is captured in its standby position by a capture means such as a hook element.

[Conventional technology and its problems]

As a manual shuttle type pallet changer of this kind, a base having a guide path provided along the direction crossing the front of the work table of the machine tool and a movably arranged on the guide path of this base. A pair of left and right pallet transfer tables are provided, and the left pallet transfer table of these pallet transfer tables is guided and moved between the left standby position and the pallet receiving / delivering position facing the front surface of the work processing table, and A shuttle type pallet changing device is known in which the right pallet carrier is also guided and moved between a right standby position and a pallet receiving / delivering position facing the front of the work processing table.

In such a shuttle type pallet changing device, the above-mentioned base is provided so as to capture the respective engaging elements of the left and right pallet transport tables in order to capture the left and right pallet transport platforms at their respective standby positions. A capture means is provided.

By the way, in such a shuttle type pallet exchanging device, while moving one of the left and right pallet conveyors between the standby position and the pallet receiving / delivering position, the other pallet conveyor is placed in the standby position. It is adapted to be in a capturing state by the capturing means. This is because if the operator operates one pallet carrier, the other pallet carrier moves, which puts the worker at risk. However, in the prior art, since the respective capturing means of the left and right pallet transport bases are manually operated by the operator and both capturing means are operated independently, one of the pallet transport bases is placed in the capturing state. There is a risk that the other pallet carrier will be released from the trapped state while inadvertently forgetting to do so. In such a state, both pallet carriers are in a moving state, which can be said to be extremely dangerous for the operator. Furthermore, in the case of this type of shuttle type pallet changing device, during the operation, the operator must alternately operate the left and right pallet transport tables, and each time the manual operation of both capture means must be performed alternately. The point that it is easy to create such a dangerous state cannot be overlooked. On the other hand, the conventional shuttle-type pallet changing device poses a problem in terms of the work efficiency of the operator in that the capturing means must be alternately operated by manual operation.

Therefore, the object of the present invention is to make it possible to cancel the trapped state of the other pallet carrier until the one pallet carrier in the non-captured state, that is, the moving state is brought into the trapped state. (EN) A pallet exchanging device, which is a shuttle type pallet exchanging device capable of greatly improving work efficiency as compared with the conventional case.

[Means for solving problems]

According to the present invention, a base having a guide path provided along a direction crossing the front surface of the workpiece processing table of the machine tool,
It is equipped with a pair of left and right pallet carriers that are movably arranged on the guideway of this base, and the left pallet carrier of these pallet carriers is a pallet receiving / facing machine that faces the left standby position and the front of the workpiece processing table. The right pallet carrier is also guided to and from the delivery position, and the right pallet carrier is also guided and moved between the right standby position and the pallet receiving / delivery position facing the front of the work processing table. In a shuttle type pallet exchanging device having a capturing means provided on the above-mentioned base so as to capture the respective engaging elements of the left and right pallet transport bases in order to capture the transport bases at their respective standby positions,
Either the left or right pallet carrier is always placed in the catching state by the corresponding catching means, and the catching means of the left and right pallet carrier is not catching the other pallet carrier is caught by the corresponding catching means. There is provided a shuttle type pallet changing device which is interlocked with each other so as to release the one pallet carrier table in the above-mentioned caught state when the pallet carrier table is caught.

In a preferred embodiment of the invention, each of the two catching means comprises a pivoting hook element adapted to catch the engaging element by the abutting action of the engaging element of the corresponding pallet carrier on the left and right. The pivot hook element is interlocked by the connecting rod member.

[Work]

In the shuttle type pallet changer according to the present invention,
The capture state of the other pallet transport table is not released as long as the capturing means of both the left and right pallet transport platforms are interlocked with each other and the pallet transport platform in the non-capture state is in the capture state.

〔Example〕

An embodiment of a shuttle type pallet changing device and a pallet carrier according to the present invention will be described below with reference to the accompanying drawings.

First, referring to FIG. 1, there is schematically shown as a plan view a relative positional relationship between a shuttle type pallet changing device 10 according to the present invention and a work processing table 12 of an automatic machine tool such as a machining center. FIG. 2 shows a side view of the pallet changing device of FIG. 1 as viewed from the left side. It should be noted that, in order to avoid complication of illustration, in FIG. 1, as a component of the pallet exchanging device 10, a base 14 fixed on an appropriate frame support structure (not shown) is used.
And a single guide path, that is, a guide rail 16 laid on the base 14 so as to cross the front surface of the workpiece processing table 10.
And a pair of left and right guide paths, that is, guide rails 18 and 20 laid on the base in parallel to the guide rail 16 and away from the front of the work processing table 12, and on the guide rails 16 and 18. Only the movably arranged left pallet carrier 22 and the right pallet carrier 24 movably arranged on the guide rails 16 and 20 are shown, the other components being omitted. Right pallet carrier 24
Can be moved between a position shown by a solid line in FIG. 1, that is, a pallet receiving / delivering position facing the front of the work processing table 12, and a right side waiting position shown by a two-dot chain line. On the other hand, the left pallet carrier 22 is shown in the left standby position in FIG. 1, but like the right pallet carrier 14, it can be moved between its left standby position and the pallet receiving / delivering position. Has become. It should be noted that each of the work machining table 12, the left pallet carrier 22 and the right pallet carrier 24 shown in a substantially rectangular shape with a chain double-dashed line shows the arrangement state of the pallets for workpiece installation.

As is clear from FIG. 1, a pair of guide rails 18 and
20 is arranged on the base 14 in such a manner that an appropriate gap is provided at a position facing the front of the work processing table 12,
The base 14 has a notch 26 that can accommodate an operator at that location.
Is formed. On the other hand, a cutout portion 28 similar to the cutout portion 26 is also formed on the base plate members of both pallet conveyors 22 and 24. These notches 26 and 28 are provided so that an operator can approach the front surface of the work processing table 12. More specifically, for example, when the pallet is transferred from the right pallet carrier 24 shown by a solid line in FIG. 1, that is, the right pallet carrier 24 located at the pallet receiving / delivering position to the work processing table 12, the worker transfers the pallet. Notch while pushing toward the work processing table 12
It is possible to penetrate into 26 and 28 and approach the front of the work processing table 12. Note that the work processing table
When receiving the pallet from 12 to the right pallet carrier 24, the operator pulls the pallet back in the notch 26 and escapes from the notches 26 and 28.

In order to move the pallet carriers 22 and 24 between their respective standby positions and the pallet receiving / delivering position as described above, each of the pallet carriers 22 and 24 is guidedly engaged with a single guide rail 16. Two guide engagement means 30 adapted to engage, and one guide engagement means 32 adapted to guide engage with a corresponding one of the pair of guide rails 18 and 20. In the present embodiment, all the guide engaging means 30 are configured in the same manner, each guide engaging means 30 is a mounting member 34 suspended from the bottom surface of the base plate of the pallet transfer table 22, 24,
A pair of horizontal guide rollers 36, 3 supported by the mounting member 34.
6 and a vertical guide roller 37 supported by the mounting member 34. As is apparent from FIGS. 1 and 2, the pair of horizontal guide rollers 36, 36 are engaged with each other in such a manner that both side surfaces of the guide rail 16 are sandwiched by the horizontal guide rollers 36, 36. Function of the guide rail 1
Constrained against horizontal movement perpendicular to 6. Further, the vertical guide roller 37 is engaged with a groove formed on one side surface of the guide rail 16, and thereby the pallet transporting bases 22 and 24 are restrained against movement in the vertical direction. On the other hand, all of the guide engaging means 32 are also configured in the same manner, and each guide engaging means 32 is supported by the mounting member 41 suspended from the bottom surface of the base plate of the pallet transfer table 22, 24 and the mounting member 41. And a vertical guide roller 42. This vertical guide roller
42 is engaged in a groove formed in the side surface of one of the corresponding one of the pair of guide rails 18 and 20, whereby the pallet transport bases 22 and 24 are restrained against vertical movement.

The point to be noted is that the guide engagement means 30 makes the pallet carrier 22
And 24 are arranged at both ends, while the guide engagement means 32 is arranged at the left end with respect to the left pallet carrier 22 and at the right end with respect to the right pallet carrier 24. Because rather than such an arrangement,
Both pallet carriers 22 and 24 are securely restrained against movements in the horizontal direction and the vertical direction excluding the left-right direction and can move in the left-right direction in a stable state, whereby the pair of guide rails 18 and This is because it becomes possible to dispose the 20 at a position facing the front surface of the work processing table 12 with an appropriate interval. When the pallet carrier is guided and supported at its four corners as in the prior art, a single guide rail such as the guide rail 16 is laid as an alternative to the pair of guide rails 18 and 20 described above. The guide rail also extends to a position facing the front of the work processing table 12. In short, in the present invention, by arranging the pair of guide rails 18 and 20 at a position facing the front surface of the work processing table 12 at intervals, the guide rail portion between them which is required in the conventional case is eliminated. As a result, the worker can approach the work processing table 12 as described above.

Referring to FIGS. 3 and 4, a portion of the pallet changer is shown in greater detail in FIG. 3 than in FIG. 1, and FIG. 4 is the same side view as FIG. However, various components are shown therein in a predetermined arrangement relationship.

In FIG. 3, the left pallet carrier 22 is shown in its standby position and the right pallet carrier 24 is shown in a pallet receiving / delivering position. A pair of bar-shaped members 35, 35 are fixed in parallel to each other on the base plates of both pallet carriers 22 and 24, and in this case, the interval is made slightly larger than the lateral width of the pallet. As shown in FIG. 3, a plurality of support rollers are provided on the inner side surfaces of the pair of rod-shaped members 35.
39 are attached at equal intervals, and the pallet is supported on these support rollers. A substantially rectangular pallet is indicated by a solid line on the left pallet carrier 22 and is denoted by reference numeral 38, while on the right pallet carrier 24, the pallet support position is indicated by a chain double-dashed line. It is shown. Further, a plurality of guide rollers 40 are attached to the upper side surfaces of the pair of rod-shaped members 35 for guiding the pallet 38 when the pallet 38 is moved on the support roller 39 and restraining the lateral movement of the pallet 38.

The operator receives the pallet 38 from the front of the workpiece processing table 12 with the left and right pallet transport tables 22 and 24 placed at the pallet receiving / delivering position, and the supporting roller 39
When the pallet 38 is moved rearward with respect to the front while being supported on the pallet, it is necessary to stop the pallet 38 at an appropriate position with respect to the pallet carrier 22 and 24 and capture the pallet 38 on the pallet 38. . For this purpose, as shown in FIGS. 3, 4 and 5, pallet carriers 22, 24
The pallet capturing means 42 is incorporated in the
The bottom surface of the is provided with an engagement element 44 adapted to engage the pallet capturing means 42. Also, pallet catching means
The reference numeral 42 also has a function of locking the pallet transfer table when the pallet transfer table 22 or 24 is placed at the pallet receiving / delivering position, and such a locking function is arranged at a predetermined position on the base 14. It is obtained by the cooperation with the locked mechanism 46. In order to avoid complication of the drawing, the fourth
In the figure, the pallet 38 itself is not shown and its engagement element 44
Only the pallet catching means 42, the pallet 38 and the locking mechanism 46 are shown in FIG. 5, and the other components are omitted.

As is apparent from FIG. 5, the pallet catching means 42 is arranged at the same position for each of the left and right pallet carriers 22 and 24. In Fig. 5, right pallet carrier
24 is located at the pallet receiving / delivering position and is in cooperation with the locking mechanism 46. On the other hand, the left pallet carrier 22 is in the left standby position.

6 and 7, the construction of the pallet catching means 42 and the locking mechanism 46 is shown in detail.

The pallet catching means 42 comprises a pivot hook element 48 which extends through a slot 50 formed in the bed of the pallet carrier 22 and 24 and is mounted on it. It is pivotally attached to the mounting portion piece 52 by means of a pivot pin 54. In particular, the mounting piece 52 is U-shaped in cross section, its two arm portions are arranged along both sides of the slot 50, and the pivoting hook element 48 is separated by its pivoting pin 54 between its two arms. Will be supported. The pivot hook element 48 includes a lower arm 56 extending substantially downward from the pivot pin 54, an upper arm 58 extending upward from the pivot pin 54, and directly below the pivot pin 54, i.e., workpiece machining. It is composed of a hook portion 60 extending toward the table 12. A stop piece 62 is attached to the upper arm portion 58, and the engagement element 44 of the pallet 38 abuts on the stop piece 62. A limiting screw 64 is screwed forward into the upper protrusion of the rear part of the mounting piece 52, which limits the clockwise pivoting movement (in FIG. 6) of the hook element 48. On the other hand, a mounting piece 68 having a U-shaped cross section similar to that of the mounting piece 52 is attached to the bottom surface of the base plate of the pallet carrier 22 or 24 in the same manner as the mounting piece 52, and is attached to the mounting piece 68. Also the limiting screw 70 is screwed forward. This limiting screw 70 allows counterclockwise pivoting movement of the hook element 48 (6th
(In the figure). It should be noted that the screwing amounts of the limiting screws 64 and 70 are adjustable, so that the pivoting range of the hook element 48 can be adjusted.

When the pallet 38 is not placed on the pallet carriers 22 and 24, the hook element 48 is placed in the abutting position with respect to the limiting screw 70, that is, the release position. When the operator supports the pallet 38 from the work processing table 12 on the support rollers 36 of the pallet transport tables 22 and 24 and moves it backward, the engaging element 44 of the pallet 38 abuts the stop piece 62, This causes the hook element 48 to pivot in the clockwise direction (in FIG. 6), causing the upper arm 58 to abut the limiting screw 64. At this time, the hook portion 60 of the hook element 48 projects from the slot 50 and takes the position as shown in FIG. 6, that is, the catching position, whereby the engaging element 44 moves between the claw of the hook portion 60 and the front surface of the upper arm portion 58. Trapped in the groove between. In short, the pallet 38 is placed on the pallet carrier 22 and 24 and the pallet capturing means 4
Will be captured by 2.

The lock mechanism 46 is a flat trapezoidal block body 72 fixed to a predetermined position of the base 14, a pair of substantially flat trapezoidal cam bodies 74 and 74 fixed to both corners on the bottom side of the block body 72, and a block. A pair of movable locking elements 78, 7 spaced apart on the top side of the body 72
Composed of 8 and. A pair of inclined cam surfaces 80, 80 is formed on each of the pair of cam bodies 74, 74.
0,80 act to engage the lower arm 56 of the hook element 48 when it assumes the catch position described above and push the hook element 48 to the catch release position. The pair of movable lock elements 78, 78 has a piston-like shape and is slidably accommodated in a bore formed in the block body 72. In FIG. 7, the movable locking elements 78, 78 are shown with their heads protruding from the bores. Elastic means, for example a coil spring (not shown), are provided in the bore for accommodating the locking elements 78, 78, such that the head of the movable locking element 78, 78 is elastically completely within the bore. It can be pushed in. Further, each of the pair of locking elements 78, 78 is formed with an inclined cam surface 82 as shown in FIG. 7, and the inclined cam surface 82 is formed on the lower arm of the hook element 48 when the hook element 48 takes the above-mentioned catching position. It engages the part 56 and acts to push the head of the corresponding movable locking element 78 into the bore described above.

When the hook element 48 is in the above-mentioned catch release position, in other words, when the pallet carrier 22 or 24 is in the pallet receiving / delivering position, the lower arm portion 56 of the hook element 48 has a pair of movable lock elements. It is placed between 78 and 78, so that the pallet carriers 22 and 24 are placed in a state of being locked against the movement in the left-right direction. That is, the pallet transporting bases 78, 78 are fixed at the pallet receiving / delivering position.
As can be seen from FIG. 6, when the hook element 48 assumes the catching position described above, its lower arm 56 has a pair of movable locking elements.
The lock state is released by coming out of the space between 78 and 78, whereby the left pallet carrier 22 can be moved leftward and the right pallet carrier 24 can be moved rightward. For example, when the left pallet carrier 22 is moved to the left after being unlocked, the lower arm 56 of the hook element 48 causes the lower cam portion 56 of the left cam body 74 (in FIG. 7) to be inclined on one of the inclined cam surfaces 80, i.e., the inner inclined cam surface 80. Engage with the hook element at this time
Although 48 will take the capture release position once, it is immediately returned to the capture position by the cam means described later. After the left pallet carrier 22 is placed at the left standby position and then moved again toward the pallet receiving / delivering position,
The lower arm 56 of the hook element 48 engages the other sloping cam surface 80 of the left cam body 74, the outer sloping cam surface 80, at which time the hook element 48 is pivoted to its uncaptured position to lower its lower arm portion. 56 engages the slanted camming surface 80 of the left movable locking element 78, which forces the head of the left movable locking element 78 into the bore described above, causing the lower arm 56 to move to the pair of movable locking elements 78. It will be locked between 78. It will be apparent that the same can be said for the right pallet carrier 24.

Referring to FIGS. 8 and 9, there is shown a pair of plate cams 84, 84 as the above-mentioned cam means, and these plate cams 84, 84 are respectively provided on the left and right pallet conveyors 22 and 24. Is arranged at a predetermined position along the movement path of the. In addition,
Each of the pair of plate cams 84, 84 is held in place by a suitable support structure (not shown). A cam surface adapted to engage with the pallet 38 itself is formed on each of the pair of plate cams 84, 84, and the cam surface is a relatively long straight line extending along the moving direction of the pallet transport bases 22, 24. A cam surface portion 86, an inclined cam surface portion 88 inclined forward from the main cam surface portion 86, and a relatively short linear cam surface portion 90 extending from the inclined cam surface portion 88 toward the pallet receiving / delivering position. Consists of. As mentioned above,
When the left pallet carrier 22 is moved to the left from the pallet receiving / delivering position after being unlocked, the hook element 48 is engaged by the lower arm portion 56 of the hook element 48 and the inner inclined cam surface 80 of the left cam body 74. Will once take the catch release position, at which time the pallet 38 will be pushed forward by the stop piece 62. However, at that time, since the pallet 38 can be engaged with the linear cam surface portion 90 of the left side plate cam 84 by the front side surface thereof, even if the pallet 38 is released from the pallet capturing means 42, the left pallet 38 is released. There is no large forward movement on the carrier 22. Immediately thereafter, the pallet 38 engages the inclined cam surface portion 88 and is pushed back backwards, at which time its engaging element 44 again abuts the stop piece 62, which causes the hook element 48 to assume the catching position again. become. Thereafter, the pallet 38 will engage the linear cam surface portion 86,
This engagement state is maintained even when the left pallet carrier 22 reaches its standby position.

Here, it should be noted that when the pallet 38 is in engagement with the linear cam surface portion 86, the pallet 38 remains abutted against the stop piece 62. In other words, the engagement element 44 of the pallet 39 is replaced by the hook element.
In order to be trapped in the groove between the claw of the hook portion 60 and the front surface of the upper arm 58 by the pivoting movement of 48, there is some play between the groove and the engaging element 44, for example of the order of 5 mm. Therefore, so-called backlash is generated in the pallet 38 during the movement by the left pallet carrier, but the pallet 38 and the linear cam surface portion 86 are engaged with each other so that the pallet 38 moves forward and backward. This means that the play of the pallet 38 with respect to the left pallet carrier 38 is substantially eliminated by being restricted to the rear limit position in the directional play. Of course, the same thing can be said about the relationship between the right pallet carrier 24 and the pallet 38.

Figures 8 and 9 also show the left and right pallet carriers.
Capture means 92 and 94 for capturing 22 and 24 at the respective standby positions, and elimination of left-right play that may occur when capturing the left and right pallet transport platforms 22 and 24 by the capture stages 92 and 94, respectively. Elastic biasing means 96 and 98 for The various components described above are omitted from FIGS. 8 and 9 in order to avoid complication of the drawing.

As shown in FIG. 9, the pallet carrier table capturing means 92 and
Each of the 94 includes hook elements 100, 100 having substantially the same configuration as the hook element 248 described above, and each hook element 100 is fixed on the base 14 at the respective standby positions of the left and right pallet transporters 22 and 24. It is pivotally mounted on the mounted mounting member 102. More specifically, each mounting member 102 is composed of a pair of plate-shaped strut elements 104, 104 (see FIG. 4), and the hook element 100 is arranged between the pair of plate-shaped strut elements 104, 104, and a pivot pin 106 is provided between them. Pivoted. Note that, in FIG. 9, in order to clearly show the hook element 100, one of the pair of plate-shaped strut elements 104, 104 is shown in a removed state. A connecting rod 108 extends between the pair of hook elements 100, 100, and the connecting rod 10
Both ends of 8 are respectively pivoted to the lower arm of the corresponding hook element 104, whereby the pallet carrier capturing means 92 and 94 are interlocked in a manner to be described later.

The left and right pallet carriers 22 and 24 are respectively provided with engaging elements 11
0 and 112, the engaging elements 110 and 112 of which are hook elements of the pallet carrier capture means 92 and 94, respectively.
It is adapted to engage 100 and be captured by its hook portion. Since the engaging elements 110 and 112 are installed on the front side of the pallet carrier bases 22 and 24 as shown by broken lines in FIG.
And 24, their engaging elements 110, 112 do not interfere with the locking mechanism 46 described above. It should be noted that, as is clear from FIG. 4, in accordance with the arrangement of the engaging elements 110 and 112, the pallet carrier table capturing means 92 is provided.
Needless to say, and 94 are also arranged on the front side of the base 14.

Each of the engagement elements 110 and 112 is slidably accommodated in the central bore of a cylindrical holder 114 arranged in the through hole of the corresponding base plate of the pallet carrier 22 or 24 so as to be slidable, and Elastic means, such as a coil spring (not shown), are provided in the bore so that the engagement elements 110 and 112 are always biased to the upper position.
In FIG. 9, the engaging element of the right pallet carrier 24 shown by a chain double-dashed line at the pallet receiving / delivering position.
112 is shown in the exact upper biased position. As best shown in FIG. 10, a cam roller 116 is mounted on top of the engagement elements 110, 112 and adapted to engage an inclined cam surface 118 formed on the bottom surface of the pallet 38. ing. That is, when the pallet 38 is moved from the work processing position onto the support roller 39 of the pallet transfer table 22, 24 at the pallet receiving / delivering position, the cam roller 116 is engaged with the inclined cam surface 118 of the pallet 38, As a result, the engaging elements 110, 112 are lowered to assume the lower position. In FIG. 9, the engagement element 110 of the left pallet carrier 22 and the engagement element 112 of the right pallet carrier 112 (shown in solid lines) are both shown in the down position. In short, when the engagement elements 110, 112 are in the above-described upward biased position, they are not captured by the hook element 100,
When the engagement elements 110, 112 are in the down position described above, they will be captured by the hook element 100.

Here, as shown in FIG. 9, the engaging element 110 of the left pallet carrier 22 is the hook element 1 of the pallet carrier catching means 92.
It is assumed that the right pallet carrier 24 is captured by 00 and is placed at the pallet receiving / delivering position indicated by the chain double-dashed line.
With the pallet 38 fully mounted on it, its engaging elements 110
When the right pallet carrier 24 is moved toward the right standby position in the manner described above, the engaging element 112 of the pallet carrier catching means 94 is assumed to be located in the lower position. It will be engaged with the hook element 100. In FIG. 9, the engaging element 112 of the right pallet carrier 24 shown by the solid line is in a state of being generally engaged with the pallet carrier catching means 94. Engagement element
When the hook element 100 of the pallet carrier catching means 94 abuts the upper arm 112, the hook element 100 is pivoted in the clockwise direction (in FIG. 9), whereby the engaging element.
112 is captured by the hook portion of the hook element 100, and the right pallet carrier 24 is in the capture position at its standby position.
On the other hand, at this time, the connecting rod 108 is moved to the left,
The hook element 100 of the pallet carrier capturing means 92 is pivoted in the clockwise direction, whereby the engaging element 110 of the left pallet carrier 22 is disengaged from the hook element 100, and the left pallet carrier 22 is captured. Is released. At this point, the left pallet carrier 22 can be moved from its standby position toward the pallet receiving / delivering position.

When the left pallet carrier 22 is placed at the pallet receiving / delivering position, the pallet 38 is delivered to the work processing table 12, and the work placed on the pallet 38 is subjected to predetermined processing. When the machining of the work is completed, the pallet 38 is placed on the left pallet carrier 22 again,
The left pallet carrier 22 is moved toward the standby position. When the left pallet carrier 22 reaches its standby position, it is brought into the catching state by the pallet carrier catching means 92, at which time the connecting rod 108 is moved to the right, and now the right pallet carrier 24 is caught. Will be canceled.

The elastic biasing means 96 and 98 are arranged on the base 14 in the relationship shown in FIG. As shown in FIG. 9, the elastic biasing means 96 is fixed to the base 14 by the column-shaped mounting members 120. In FIG. 9, the elastic biasing means 98 is not shown in order to avoid complication of the drawing, but the elastic biasing means 98 is also elastically biased at a position corresponding to the position shown in FIG. It is fixed to the base 14 in the same manner as the means 96. The elastic biasing means 96 and 98 include spring biased moveable portions 122 and 124, respectively. Left and right pallet carrier
The abutment pieces 126 and 1 are attached to the bottom of the base plates of 22 and 24, respectively.
28 is attached so that the abutting pieces 126 and 128 can abut the movable parts 122 and 124, respectively.

As in the case of the pallet catching means 48 described above, in the case of the pallet carrying table catching means 92 and 93, the engaging elements 110, 112 are caught by the corresponding hook element 100 with play in the left-right direction, so that the pallet carrying boards 22, 24 are provided. However, even if the pallet is caught at the standby position, so-called looseness will occur on the pallet transport tables 22 and 24. Therefore, elastic biasing means 9
6,98 is an abutting piece 12 in order to eliminate such backlash.
Work with 6,128. In detail, when the engaging element 110 of the left pallet carrier 22 is captured by the hook element 100 of the pallet carrier capturing means 92 as shown in FIG. 9, the abutting piece 126 is elastically biased 96. Is placed in an abutting state with the movable part 122 of the left pallet carrier 22 via the abutting piece 126.
Is pushed to the right, so that the left pallet carrier 22 is restricted to the limit position in the direction toward the pallet receiving / delivering position in the left and right play, and the backlash in the left and right direction is eliminated. Of course, the same thing can be said for the right pallet carrier 24.

Further, when the elastic biasing means 96, 98 move the pallet transporting bases 22, 24 from the pallet receiving / delivering position to reach the corresponding standby position, the pallet transporting bases 22, 24 are stopped and their collision energy is reduced. It will be obvious that it also has a function as a stop and damper that absorbs.

In the above-mentioned embodiment, both pallet carrier capturing means are interlocked with each other by the link mechanism using the connecting rod. However, if necessary, a hook request of the pallet carrier capturing means may be transmitted by an electromagnetic solenoid or the like. Alternatively, the operation of the electric means may be linked by the switch means associated with the movement of the pallet carrier.

[Effect]

As is clear from the above description, in the shuttle type pallet exchanging device according to the present invention, the capturing means of both the left and right pallet conveyors are interlocked with each other, and one of the pallet conveyors in the non-capturing state is in the capturing state. By placing the pallet on the other side, the trapped state of the other pallet carrier is automatically released, so the safety of the worker is guaranteed and the work efficiency of the worker is greatly improved. .

[Brief description of drawings]

1 is a plan view showing an embodiment of a shuttle type pallet changing device according to the present invention, FIG. 2 is a left side view of the shuttle type pallet changing device of FIG. 1, and FIG. 3 is a shuttle type pallet of FIG. FIG. 4 is a partially enlarged plan view of the exchanging device, FIG. 4 is an enlarged detailed view of FIG. 2, and is a view showing the arrangement relationship of various components when the shuttle enlarging pallet exchanging device is viewed from the side;
FIG. 5 is a front view of FIG. 3, showing the positional relationship between the pallet catching means and the lock mechanism, and FIG. 6 is an enlarged view of the pallet catching means and the lock mechanism shown in FIG. Fig. 7 is a side view, Fig. 7 is a front view of Fig. 6, and Fig. 8 is a plan view corresponding to the plan view of the shuttle type pallet changing device shown in Fig. 1. A cam, an engagement element adapted to engage with the pallet carrier base capturing means, an elastic biasing means for eliminating play of the pallet carrier base, and an abutting adapted to engage with the elastic biasing means. FIG. 9 is a front view of FIG. 8 showing a positional relationship with the pallet, and is a front view of FIG. 8 and shows an arrangement of a pallet carrier base capturing means and an engaging element adapted to engage with the pallet carrier base capturing means. FIG. 10 is a diagram showing the relationship, and FIG. 10 is for engaging with the pallet carrier capturing means shown in FIG. It is a cross-sectional enlarged side view partially showing an engagement state between the inclined cam surface of the top portion and the pallet bottom surface of the turned engagement elements. 10 …… Shuttle type pallet changer, 12 …… Machine tool work table, 14 …… Base, 16,18,20 …… Guide rails, 22,24 …… Pallet carrier, 26,28 …… Incision Part, 30, 32 …… guide support means, 42 …… pallet catching means, 46 …… lock mechanism, 48 …… hook element, 78 …… lock element, 84 …… plate cam, 92,94 …… pallet carrier Capturing means, 96,98 ... elastic biasing means, 110,112 ... engaging elements, 126,128 ... butting pieces.

Claims (2)

[Claims] 1. A base having a guide path provided along a direction crossing a front surface of a work machining table of a machine tool, and a pair of left and right pallet conveyors movably arranged on the guide path of the base. Of these pallet carriers, the left pallet carrier is guided and moved between the left standby position and the pallet receiving / delivering position facing the front of the work processing table, and the right pallet carrier also waits on the right side. It is configured to be guided and moved between a position and a pallet receiving / delivering position facing the front surface of the work processing table, and the left and right pallet transporting bases are set to capture the left and right pallet transporting bases at respective standby positions. In the shuttle type pallet changing device provided with a catching means provided on the base so as to catch each of the engaging elements, Either one of the pallet transporting bases is always placed in the capturing state by the corresponding capturing means, and the other pallet transporting bases in which the capturing means of the left and right pallet transporting bases are in the non-capturing state are captured by the corresponding capturing means. A shuttle type pallet exchanging device, wherein the shuttle type pallet exchanging devices are interlocked with each other so as to release one of the pallet transporting bases in the above-mentioned capturing state. 2. The shuttle type pallet changing device according to claim 1, wherein each of the both catching means is engaged by an abutting action with an engaging element of the right and left corresponding pallet carrier. A shuttle-type pallet changer comprising pivoting hook elements adapted to capture the elements, the pivoting hook elements being interlocked by a connecting rod member.