Clamping system suitable for machine tool

Abstract

The invention relates to a clamping system comprising a chuck and a tray for mounting an object thereon. The chuck comprises a plurality of chuck reference elements in the X, Y and Z directions, the tray comprises a plurality of tray reference elements in the X, Y and Z directions, a tray locking mechanism is arranged on the tray, and a chuck locking mechanism is arranged on the chuck. Wherein the tray can be clamped to the chuck by interaction of the tray locking mechanism with the chuck locking mechanism, and wherein the tray reference element is aligned with the chuck reference element in the X, Y and Z directions when the tray is clamped to the chuck. The tray includes a vacuum ejector for generating a vacuum and a tray suction opening in communication connection with the vacuum ejector for holding the object positioned on the tray by the generated vacuum.

Description

Technical Field

[0001] The present invention relates to a clamping system for a machine tool, comprising a chuck and a pallet that can be clamped onto the chuck. In particular, the pallet is suitable for receiving an object such as a workpiece thereon, and the chuck is suitable for being mounted on a machine table. Background Art

[0002] Clamping systems are widely used in machining areas such as milling, turning, EDM or laser machining. Such machining processes are carried out by machines. In order to hold the workpiece or machining tool securely in the machine, a clamping system is essential, as high forces may be exerted on the workpiece or machining tool.

[0003] In order to ensure adequate machining, it is important to have a clamping system that can quickly clamp and release the workpiece or machining tool without wasting too much machine time. The clamping system includes a chuck and a pallet that can meet this requirement. The chuck is usually mounted on the machine table. Before machining, the workpiece can be pre-mounted on the pallet. The pallet with the workpiece on it can be clamped into the chuck and released from the chuck very quickly. Usually, the pallet can be quickly connected to and disconnected from the chuck. In addition, the connection and disconnection can even be automated, for example using a robot to save time.

[0004] US 9108286 B2 discloses a clamping device for a tool or workpiece. The clamping device includes at least one chuck and at least one holder for a workpiece or tool. The holder has an upper portion and a hollow tubular extension. The upper portion is detachably connected to the hollow tubular extension so that the hollow tubular extension remains hollow when connected to the upper portion. The upper portion defines a flat upper surface for mounting a tool or workpiece thereon.

[0005] US 8413973 discloses a clamp comprising a chuck and a clamping tray detachably fixed to the chuck. The chuck is provided with four centering pins, which are arranged on the chuck and cooperate with the centering openings arranged on the clamping tray so that the clamping tray is oriented in the X and Y directions when clamped in the chuck.

[0006] All of these clamping systems provide a quick and secure clamping function between the pallet and the chuck. However, the known clamping systems require manual operation to fix the workpiece to the pallet by means of fixing devices such as screws. After processing, the processed workpiece must be removed from the pallet by loosening the fixing devices. This manual operation is time-consuming. Summary of the invention

[0007] The object of the present invention is to provide a clamping system with a chuck and a tray so that an object can be automatically fixed on a tray. In particular, the object of the present invention is to provide a clamping system with a chuck and a tray so that an object can be quickly installed on and removed from the tray.

[0008] According to the invention, these objects are achieved by the features of the independent claims.Further advantageous embodiments can be derived from the dependent claims and the description.

[0009] According to the present invention, the clamping system includes a chuck and a tray for mounting an object thereon. The chuck includes a plurality of chuck reference elements in the X, Y and Z directions. The tray includes a plurality of tray reference elements in the X, Y and Z directions. A tray locking mechanism is provided on the tray, and a chuck locking mechanism is provided on the chuck. The tray can be clamped to the chuck by the interaction of the tray locking mechanism and the chuck locking mechanism. When the tray is clamped to the chuck, the tray reference element is aligned with the chuck reference element in the X, Y and Z directions. The tray includes a vacuum ejector for generating a vacuum and a tray suction opening connected to the vacuum ejector, for keeping the object positioned on the tray by the generated vacuum.

[0010] The clamping system is used to hold the object to be processed, such as a workpiece, on the machine table for processing. During the processing, high cutting forces may be exerted on the workpiece. These high cutting forces are also transmitted to the clamping system that holds the workpiece on the processing table. Therefore, the clamping system must be rigid and must be able to withstand the applied forces in order to reliably keep the workpiece positioned throughout the processing. The pallet and / or the chuck can be made of aluminum or high-alloy steel. For such a clamping system, it is important to accurately position the pallet and chuck relative to each other. Therefore, reference elements are indispensable. Stable and precise reference systems can reduce the idle time of the machine. Therefore, reference elements are provided in the x, y and z directions in order to accurately determine the position of the pallet. The reference system minimizes the setup time, increases the machine's throughput and provides the basis for automated production. Fast and precise pallet changes can be achieved. This ensures high repeatability and high-precision positioning. Preferably, the reference element in the Z direction is automatically cleaned by air jets through a nozzle in the Z reference of the chuck.

[0011] In particular, such clamping systems are often used with automated systems for automatically changing pallets. Therefore, the pallet locking mechanism and the chuck locking mechanism are designed to achieve fast and reliable clamping. The pallet locking mechanism can include a tie rod with a floating bayonet joint. By clamping the tie rod, it interacts with the chuck locking mechanism. However, other pallet locking mechanisms can also be applied to the clamping system of the present invention.

[0012] Typically, before machining, the chuck is mounted on the machine table. If the machining object is a workpiece, it is mounted on a pallet in advance. In particular, in the preparation stage before machining, multiple workpieces are mounted on multiple pallets so that the pallets with the workpieces can be quickly replaced during machining to ensure machining efficiency. However, the workpiece must be manually fixed to the pallet, such as by screws. Therefore, it takes extra time to mount the workpiece on the pallet, thus increasing the machining cost. Applying vacuum to hold the workpiece is a quick and safe solution. A clamping system with a vacuum ejector in the pallet can further improve machining efficiency and reduce costs.

[0013] The vacuum ejector is designed to generate a vacuum based on, for example, the Venturi effect. The vacuum ejector has a tubular body. A working fluid is fed into the vacuum ejector and flows through the tubular body having narrow and wide cross-sectional areas. The velocity of the working fluid is affected by the different cross-sectional areas. The working fluid flows out of the vacuum ejector at a high velocity, thus resulting in a low pressure in the vacuum ejector. In this way, a vacuum is generated. The working fluid may be a liquid or pressurized air. In a preferred variant, pressurized air is used as the working fluid. Alternatively, nitrogen is used as the working fluid. Pressurized air is easier to handle than liquids. In addition, since the chuck is a pneumatic chuck, pressurized air is supplied into the chuck. In this way, no additional piping is required to supply the working fluid from the outside into the vacuum ejector. The vacuum ejector comprises an ejector inlet for supplying the working fluid, an ejector outlet for discharging the working fluid, and an ejector adsorption opening.

[0014] In some embodiments, the tray is provided with a groove arranged inside the tray for arranging the vacuum ejector therein, in particular, the longitudinal direction of the groove is parallel to the top surface of the tray. In this way, the vacuum ejector is completely embedded in the tray.

[0015] In some embodiments, the pallet is provided with an air inlet for supplying compressed air into the vacuum ejector, and the air inlet is arranged in such a way that when the pallet is clamped to the chuck, the compressed air supplied into the chuck automatically enters the air inlet.

[0016] Preferably, the air inlet is arranged on the bottom surface of the tray, and in addition, the air supply outlet is arranged on the top surface of the chuck, and when the tray is clamped with the chuck, the air inlet of the tray is automatically aligned with the air supply outlet of the chuck. This provides a simple structure for supplying compressed air into the tray. Since there is no need to connect an additional pipe to the tray from the outside, it is ensured that the tray is automatically replaced by, for example, a tray changer. The air inlet can be a hole. At least one air channel can be formed in the tray to connect the air inlet to the ejector air inlet. The air supply outlet on the chuck can also be a hole connected to an air channel formed in the chuck, in which compressed air can flow. Usually, compressed air is supplied from an external pipe to the chuck to clamp the tray. The chuck is often installed on the machine table and cannot be replaced frequently. During the processing, the tray must be frequently replaced. Therefore, the tray must be able to be automatically replaced to improve the processing efficiency. Therefore, it is advantageous to provide a tray without an external connection to the pipe. Preferably, the connection of the air inlet on the tray and the air outlet on the chuck is sealed by a seal, such as a sealing ring. Preferably, the connection is sealed on the tray and / or on the chuck.

[0017] In one variant, the tray suction opening is covered by a filter, in particular a mesh filter. This prevents dirt or debris generated by processing from falling into the suction opening. In particular, a sealing element is arranged around the tray suction opening to ensure suction when an object is placed on the tray suction opening.

[0018] In an advantageous variant, the pallet sensing mechanism is integrated in the pallet and the chuck sensing mechanism is integrated in the chuck, wherein the pallet vacuum sensing mechanism and the chuck sensing mechanism are configured such that they are automatically aligned when the pallet is clamped with the chuck. In particular, the pallet sensing mechanism and the chuck sensing mechanism are adapted to monitor the state of the vacuum generated by the vacuum ejector, e.g. it can detect whether the vacuum pressure is maintained during machining. For safety reasons, it is advantageous to monitor the state of the generated vacuum in order to be able to react if the vacuum state is not good.

[0019] Preferably, the tray sensing mechanism comprises a tray sensing hole, which is disposed on the bottom surface of the tray and is communicatively connected to the tray adsorption opening.

[0020] In addition, a chuck sensing hole is provided on the top surface of the chuck, and when the pallet is clamped with the chuck, the pallet sensing hole is automatically aligned with the chuck sensing hole. Typically, a vacuum detection device is arranged outside the clamping system, such as in a cabinet or a robot cabinet, to monitor the clamping state of the chuck. Arranging the sensing hole on the pallet can benefit from existing devices because the vacuum state at the chuck sensing hole can be monitored by the vacuum detection device. When the pallet sensing hole is aligned with the sensing hole of the chuck, the vacuum state at the pallet sensing hole can be measured by a detection device arranged, for example, in a cabinet or a robot cabinet.

[0021] In some embodiments, an ejector inlet connected to the groove is provided on the surface of the tray for inserting the vacuum ejector into the groove arranged inside the tray, and the ejector can be covered with a cover having an air outlet formed thereon. The air outlet is connected to the ejector outlet to discharge air from the ejector to the outside of the tray.

[0022] In a preferred variant, the ejector suction opening is connected to the tray suction opening via at least one channel and / or at least one hole. Depending on the size of the tray, the tray suction opening may have different sizes and / or shapes. In most applications, the dimensions of the tray suction opening differ from the dimensions of the ejector suction opening. Furthermore, the ejector suction opening may be located at different locations inside the tray. Therefore, some connecting element is required to connect the ejector suction opening to the tray suction opening.

[0023] In some embodiments, the clamping system further comprises a fixture for mounting on a pallet to hold the workpiece, wherein the fixture has at least one fixture suction opening connected to the pallet suction opening. Sometimes, the fixture is first mounted on the pallet and the workpiece is mounted on the fixture in order to provide greater flexibility for customers using the clamping system. The fixture is designed in such a way that the vacuum generated in the pallet can reach the fixture and be distributed in different areas of the fixture. The pallet vacuum suction opening is connected to the fixture suction opening through a channel, in particular a channel formed at the bottom of the fixture.

[0024] In a preferred variant, the clamp comprises at least two clamp suction openings for providing at least two suction areas, and a plurality of clamp sealing grooves, wherein the clamp sealing elements can be inserted into the clamp sealing grooves for selectively activating the clamp suction areas. Alternatively, sealing slots or sealing holes can be applied instead of sealing grooves. The clamp sealing elements can be O-rings or other sealing devices.

[0025] In an advantageous variant, a liquid chamber is arranged below the tray suction opening for storing liquid entering through the tray suction opening.

[0026] Preferably, a second valve is mounted at one end of the liquid chamber to close or open the liquid chamber. During processing, liquid may enter the tray through the tray suction opening, which can have a negative impact on the suction function. The liquid should be evacuated from time to time to avoid clogging the ejector. Arranging the valve at the output end of the liquid chamber enables automatic emptying of the liquid chamber. The valve can be controlled by a control unit, which also controls the clamping system. When the vacuum is activated, the valve is closed, and when the vacuum is not activated, the valve is open to allow the liquid to flow out.

[0027] In the present invention, the clamping system refers to the first clamping system or the second clamping system. The first clamping system and the second clamping system refer to two different embodiments of the clamping system. The first clamping system is smaller than the second clamping system. However, the vacuum ejector can also be applied to other clamping systems, not just these two clamping systems. For the sake of clarity, all elements of the first clamping system are represented by the term "first", and all elements of the second clamping system are represented by the term "second". The general terms used in the present invention shall include elements represented by the terms "first" and / or "second".

[0028] In particular, the vacuum ejector refers to the first vacuum ejector or the second vacuum ejector, and the vacuum ejectors may have different sizes. All vacuum ejectors that can be installed inside the tray and can provide the required pressure may be applicable to the present invention, for example, the second tray is larger than the first tray, so the second vacuum ejector is larger than the first vacuum ejector. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The following further describes a more specific description of the present invention. The embodiments are described in detail and explained with reference to the accompanying drawings, in which:

[0030] Figure 1 A three-dimensional view of a first tray is shown;

[0031] Figure 2 shows a side view of a first tray;

[0032] Figure 3 shows a bottom view of a first tray;

[0033] Figure 4 shows a top view of a first tray;

[0034] Figure 5 shows a side view of the first tray with a cutaway view of the vacuum ejector;

[0035] Figure 6a , Figure 6b The application of the first clamping system in an unclamped state and a clamped state are respectively shown;

[0036] Figure 7a , Figure 7b Another application of the first clamping system in an unclamped state and a clamped state is shown respectively;

[0037] Figure 8 A three-dimensional view of the second tray is shown;

[0038] Fig. 9 shows a side view with partial section of a second tray;

[0039] Fig.10 shows a top view of the second tray;

[0040] Fig.11a , Fig.11b shows a cross-sectional view of the second tray;

[0041] Fig.12 showing a cross-sectional view of a portion of a second tray;

[0042] Fig.13 shows a bottom view of the second tray;

[0043] Fig.14a , Fig.14b The application of the second clamping system in an unclamped state and a clamped state are respectively shown;

[0044] Fig.15a , Fig.15b Another application of the second clamping system in an unclamped state and a clamped state is shown respectively;

[0045] Fig.16a , Fig.16b and Fig.16c An example of selecting an adsorption area is shown. DETAILED DESCRIPTION

[0046] Figures 1 to 5 A first tray for a first clamping system is shown.

[0047] Figure 1 A three-dimensional view of a first tray 30 for a first clamping system of the present invention is depicted. The first tray has a circular shape and a defined height. However, the tray may have a shape different from that shown in the figure. A first vacuum ejector is integrated into the first tray. On the side of the first tray, i.e., on its periphery, a first ejector inlet 35 is provided. The first vacuum ejector is inserted into the first tray through the first ejector inlet and embedded in the first tray. When the first vacuum ejector is inserted into the first tray, the first ejector inlet is covered by a first cover 35b to prevent the first vacuum ejector from falling out of the first tray. A first air outlet 35a is provided on the first cover so that the air flowing out of the first vacuum ejector can flow out of the first tray. A first tray suction opening 36 is arranged on the top surface of the first tray and is connected to the first vacuum ejector inside the first tray. A first pair of slots 31a, 31b and a first groove 32 are formed on the side of the first tray for automatic manipulation. A robot can grab the first tray at this position so as to automatically mount and remove the first tray from the first chuck.

[0048] like Figure 2, a side view of the first tray is shown, which is made in one piece. However, it can be divided into two parts in its height (Z direction), namely an upper part 33 and a lower part 34. The lower part is mainly used to interact with the chuck locking mechanism of the first chuck. When the first tray is clamped into the first chuck, the lower part is located inside the first chuck, while the upper part is located outside the first chuck, as shown in FIG. Figure 7b As shown. The first pair of slots and the first groove for automatic manipulation are usually arranged on the upper part of the first pallet so that the robot gripper can also reach the slots and the groove in the clamped state. In the example shown in the figure, the first vacuum ejector is received in the upper part of the first pallet. However, it is not excluded to embed the first vacuum ejector in the lower part of the first pallet.

[0049] Figure 3 A bottom view of a first pallet is shown. Pallet reference elements are arranged on the pallet in the X, Y and Z directions. They are defined as pallet X reference elements, pallet Y reference elements and pallet Z reference elements. A plurality of pallet X reference elements 37a, 37b, 37c, 37d, a plurality of pallet Y reference elements 40a, 40b, 40c, 40d and a plurality of pallet Z reference elements 38a, 38b, 38c, 38d, 38e, 38f, 38g, 38h are arranged on the bottom surface of the first pallet. Figure 3 In the variant shown, these reference elements are manufactured separately on a thin plate and fixed to the first tray. However, it is also possible to form all the reference elements directly on the first tray, forming an integral body. Reference elements in the X, Y and Z directions are also provided on the first chuck. They are defined as the chuck X reference element, the chuck Y reference element and the chuck Z reference element. Figure 6a As shown, a plurality of chuck X reference elements 12a, 12b, 12c, 12d, a plurality of chuck Y reference elements 11b, 11c, 11d and a plurality of chuck Z reference elements 13a, 13b are arranged on the top surface of the first chuck 10. Figure 6a Not all reference elements are marked in FIG. Typically, there are the same number of reference elements on the first tray and on the first chuck.

[0050] Figure 4 A top view of a first tray is depicted. Figure 5 Shown along Figure 4. The first vacuum ejector 42 has an elongated body and is located on a plane parallel to the top surface of the first tray so that the height of the tray does not increase. However, it is not excluded to arrange the first vacuum ejector in another direction. In addition, the vacuum ejector extends from the first ejector inlet 35 to the center of the first tray. The first vacuum ejector has a first ejector inlet, a first ejector outlet and a first ejector adsorption opening. In this example, pressurized air is the power fluid of the vacuum ejector. In order to avoid an additional pipeline for supplying pressurized air to the vacuum ejector, the first ejector inlet is connected to the first air inlet 43 through a first air channel 46, so that the pressurized air provided to the first chuck can be used. In this way, no additional external pipeline is required to supply compressed air to the ejector. This is conducive to realizing automatic replacement of the tray. The first air inlet 43 is set to a position where compressed air from the first chuck can be automatically supplied to the first air inlet. Therefore, in this example, the first air inlet 43 is formed as a hole on the bottom surface of the first tray and is connected to the first air channel 46. The first chuck is provided with a first air supply outlet on its top surface. When the first pallet is clamped to the first chuck, the first air inlet 43 of the first pallet is precisely aligned with the first air supply outlet of the first chuck, so that the compressed air supplied to the first chuck can further flow into the ejector through the air channel in the chuck, the first air supply outlet of the chuck, the first air inlet of the first pallet and the first air channel of the first pallet.

[0051] The first ejector adsorption opening is connected to the first tray adsorption opening 36 via a first vacuum suction channel 47a and a first vacuum hole 45 embedded in the first tray. One end of the first vacuum suction channel is directly connected to the ejector adsorption opening. The first vacuum hole is drilled in a substantially vertical direction to connect the tray adsorption opening and the first vacuum channel. On the one hand, the adsorption opening on the surface of the tray should be large enough to provide a large area through which the object can be vacuum adsorbed. On the other hand, drilling a large hole in the tray should be avoided. Providing a first vacuum hole can meet these two requirements because it transmits the generated vacuum from the ejector to the tray adsorption opening, and the first vacuum hole is much smaller than the first tray adsorption opening. However, the first vacuum channel can also be directly connected to the first tray adsorption opening.

[0052] The security of the clamping state is also important to ensure the correct machining process, so it is necessary to ensure that the workpiece is properly held by the vacuum generated by the vacuum ejector. Therefore, monitoring the vacuum generated by the vacuum ejector can improve the reliability of the system and the security of the machining. Figure 4As shown, a vacuum sensing device is provided in the first pallet. A first sensing hole 49 is formed on the bottom surface of the first pallet. The first sensing hole is connected to the first vacuum suction channel. Therefore, the vacuum sensed at the position of the first sensing hole also represents the vacuum condition generated by the ejector. One end of the first sensing hole 49 for monitoring the vacuum is formed on the bottom surface of the first pallet so that it can be aligned with the sensing hole formed on the first chuck. When the chuck is mounted on the machine workbench, the vacuum sensing device provided in the machine workbench can be connected to the vacuum sensing hole on the chuck, and by clamping the first pallet to the first chuck, the vacuum sensing device can be further automatically connected to the first sensing hole 49 of the first pallet. In this way, no additional sensing device is required in the clamping system.

[0053] exist Figure 4 In the embodiment shown, the first sensing hole 49 is not directly connected to the first vacuum suction channel 47a, but is directly connected to the first tray adsorption opening through the first vacuum connection hole 44 and the first vacuum sensing channel 47b. Figure 4 As shown, a first plug 48 is arranged in a vertical direction at one end of the first vacuum suction channel to further cut off the vacuum flow in the direction of the sensing hole. The first vacuum connection hole is arranged in a vertical direction to connect the first tray adsorption opening to the first vacuum sensing channel 47b, and the first sensing hole is connected to the first vacuum sensing channel 47b. This arrangement is to further improve the reliability of vacuum monitoring. Basically, the first vacuum suction channel 47a and the first vacuum sensing channel 47b can be regarded as one channel, which is cut into two sections by the first plug.

[0054] Figure 6a and 6b One application of the first clamping system is shown, which includes the first pallet 30 and the first chuck 10. When the workpiece is positioned on the first pallet vacuum opening 36, the workpiece 2 may be directly held by the first pallet by the vacuum generated by the first vacuum ejector.

[0055] Figure 7a and 7b Another application of the first clamping system is shown, wherein a first clamp 20 is arranged between a first pallet and a workpiece. Figure 7aA three-dimensional view of a first clamping system 1 is shown, wherein the first clamp is in an unclamped state. This example shows an application for clamping a workpiece on a machine table. The first chuck 10 can be mounted on a machine table, not shown. The first pallet 30 can be clamped into the chuck by a tie rod 50. In this example, a tie rod is provided for connecting the first chuck and the first pallet, but the use of the tie rod is not mandatory, as other locking mechanisms can also be used to clamp the chuck and the pallet. On top of the first pallet, a first clamp can be mounted. The first clamp has at least one first clamp suction opening 21, 22, 23, 24 for allowing vacuum to pass through the opening to hold the workpiece mounted thereon. The first clamp suction opening is a through hole. In addition, a plurality of clamp channels are formed on the bottom surface of the first clamp for connecting the first clamp suction opening with the first pallet suction opening. In this way, the vacuum generated by the vacuum ejector can reach the workpiece through the first pallet suction opening and the clamp opening. In addition, different suction areas can be activated by inserting the first clamp seal into the sealing groove 25 in the first clamp. For example, Figure 7a The first jig shown has four first jig suction openings, and therefore the entire surface of the jig can be divided into four suction areas, each of which is defined around one first jig suction opening.

[0056] Figure 7b The state is shown when the workpiece is held on the first fixture by vacuum and the first pallet is clamped into the first chuck.

[0057] Several sealing members, such as O-rings, are arranged around the first tray suction opening and the first fixture suction opening for sealing.

[0058] Figures 8 to 12 A second tray of a second clamping system of the present invention is shown. The second clamping system is larger than the first clamping system.

[0059] Figure 8 1 shows a three-dimensional view of a second tray 130 suitable for the second clamping system of the present invention. The tray has a rectangular shape and a certain height. However, the second tray can have a shape different from that shown in the figure. Fig. 9As shown, a second vacuum ejector 142 is integrated inside the second pallet. On the side of the second pallet, that is, on its periphery, a second ejector inlet 135 is provided. When the second vacuum ejector is inserted into the second pallet, the second ejector inlet is covered by a second cover 135b to prevent the second vacuum ejector from falling out of the second pallet. A second air outlet 135a is provided on the second cover so that the pressurized air discharged from the second vacuum ejector flows out of the second pallet. The vacuum ejector is inserted into the second pallet through the second ejector inlet and embedded in the second pallet 135. The second pallet suction opening 136 is arranged on the top surface of the second pallet and is connected to the vacuum ejector inside the second pallet. A pair of second pallet grippers 131 are formed on the side of the second pallet for automatic manipulation. A robot can grasp the second pallet at this position for automatic installation and removal of the pallet.

[0060] like Fig. 9 As shown, a side view and a partial cross-sectional view of the second tray are shown, and the second tray is made into an integral type. The second vacuum ejector 142 is completely embedded in the second tray. The second vacuum ejector has an elongated body and is located on a plane (e.g., an XY plane) parallel to the top surface of the second tray. In addition, the vacuum ejector extends from the ejector inlet 135 to the center of the second tray. The second vacuum ejector has a second ejector inlet 142a, a second ejector outlet 142b, and a second ejector adsorption opening 142c. In this example, pressurized air is the power fluid of the vacuum ejector. In order to avoid using an additional pipeline to supply pressurized air to the second vacuum ejector, the second ejector inlet is connected to the second air inlet 143 through a second air channel 146 so that the pressurized air supplied to the second chuck can be used. The second air inlet 143 is arranged so that when the second tray is clamped to the second chuck, it can be automatically connected to the position of an air channel or air outlet embedded in the second chuck. Therefore, in this example, the second air inlet 143 is formed as a hole from the bottom surface of the second tray in a vertical direction (Z direction) to the second air channel 146. The second air channel can have different shapes depending on the position of the second air inlet 143 and the second injector inlet 142a. The air channel of the second chuck has an air outlet on the top surface of the second chuck, which is not shown in the figure. When the second pallet is clamped into the second chuck, the second air inlet of the second pallet is aligned with the air outlet of the second chuck, so that pressurized air can be fed into the injector through the air channel of the second chuck, the air outlet of the second chuck and the second air inlet of the second pallet. The second injector can also be arranged at a position where the second air inlet can be directly connected to the second injector air inlet to save the second air channel.

[0061] For the second clamping system, a reference element is also required. Fig.131 shows a bottom view of the second tray. A plurality of X reference elements 138, a plurality of Y reference elements 137 and a plurality of Z reference elements 140 are arranged on the bottom surface of the second tray. In particular, all reference elements are directly integrally formed with the second tray. The reference elements can also be formed separately and mounted on the tray. Reference elements are also arranged on the second chuck. Fig.15a As shown, a plurality of X reference elements 112 , a plurality of Y reference elements 111 , and a plurality of Z reference elements 113 are disposed on the top surface of the second chuck 110 .

[0062] Fig.10 A top view of the second tray is depicted.

[0063] Means for monitoring the vacuum generated by the second vacuum ejector are also provided in the second tray. Fig.13 A second sensing hole 144 formed on the bottom surface of the second tray is shown to monitor the state of the vacuum. The second sensing hole can also be aligned with the sensing hole on the second chuck. When the second chuck is mounted on the machine workbench, the vacuum sensing device arranged in the cabinet can be communicatively connected to the vacuum sensing hole on the second chuck, and further communicatively connected to the second sensing hole 144 of the second tray. In this way, no additional sensing device is required. In this example, the second vacuum channel 145 connects the second ejector adsorption opening 142c to the second tray vacuum opening 136. In addition, a second vacuum sensing channel 147 is formed on the extension of the second vacuum channel, but the second vacuum sensing channel 147 is separated from it by a second plug 148. The second sensing hole is drilled in the vertical direction (Z direction) to reach the second vacuum sensing channel. The second sensing hole is not directly connected to the second vacuum channel, but is directly connected to the second tray adsorption opening through the second vacuum connection hole 151 and the second vacuum sensing channel. In particular, the second vacuum connection hole is opened vertically downward from the second adsorption opening to the second vacuum sensing channel, such as Fig.11b shown.

[0064] During processing, if the seal around the second suction opening is not perfect, liquid may flow into the second suction opening. This will have a negative impact on the suction function. Therefore, if Fig.12 As shown, a liquid chamber 70 is formed below the second adsorption opening in the second tray. Fig.12 is along Fig.10 13. The liquid chamber extends downward from the second suction opening. A second valve 71 is arranged at the end of the liquid chamber near the bottom surface of the second tray 132 to allow the liquid to be automatically emptied from the liquid chamber when the vacuum is deactivated. This further ensures automatic manipulation of the tray because the liquid chamber does not have to be manually emptied by the operator. When the second tray is unloaded or the vacuum pressure is deactivated, the second valve can be automatically opened and the liquid stored in the chamber can flow out from the bottom of the second tray.

[0065] Fig.14a and 14b An application of the second clamping system including the second tray 130 and the second chuck 110 is shown. When the workpiece 2 is located on the second vacuum opening 136, the workpiece 2 can be directly held by the second tray by the vacuum generated by the second vacuum ejector. No additional clamp is required. In this way, the workpiece can be easily mounted on and removed from the tray, and it is possible to use an automatic handling tool.

[0066] Fig.15a and 15b Another application of the second clamping system is shown, wherein a second clamp 120 is arranged between the second pallet and the workpiece. Fig.15a A three-dimensional view of the second clamping system 100 is shown, wherein the second clamp is in an unclamped state. This example shows an application for clamping a workpiece on a machine table. The second chuck 110 can be mounted on the machine table. The second pallet 130 can be clamped into the second chuck by a clamping mechanism. In this example, the clamping mechanism 150 integrated in the second chuck is suitable for connecting the second chuck and the second pallet, but it is not mandatory to use this type of clamping mechanism, because other clamping mechanisms (such as a drawbar) shown in the first clamping system are also suitable for clamping the second chuck and the second pallet.

[0067] A second fixture may be mounted on top of the second pallet. The second fixture has at least one second fixture adsorption opening 121, 122, 123, 124 for allowing vacuum to pass through to hold the workpiece mounted thereon. The second fixture adsorption opening is a through hole. In addition, a plurality of fixture channels are formed on the bottom surface of the second fixture. When the second fixture is fixed to the second pallet, the second vacuum opening 136 of the second pallet may be connected to the second fixture adsorption opening through the fixture channel. In this way, the vacuum generated by the vacuum ejector may reach the workpiece through the second pallet adsorption opening and the fixture opening. In addition, different adsorption areas may be activated by inserting a fixture sealing element into the second fixture groove 125 on the second fixture.

[0068] To fasten the clamp to the pallet, different connection mechanisms can be used. Figure 7a A variant of tightening the first clamp on the first pallet is shown. Fig.15a Another variation is shown in which the second fixture is clamped on the second tray by two additional chucks (third chuck 141a and fourth chuck 141b). In this variation, the first valve 60 is arranged in the second tray, such as Fig.11b As shown, Fig.11b is along Fig.13A cross-sectional view cut along the line HH shown in . The first valve is configured to automatically close if air is supplied, and to open if the air stops. The third chuck 141 and the fourth chuck used to clamp the second fixture on the second pallet also require pressurized air, so pressurized air must also be supplied to these two chucks. The second sensing hole 144 is also used to supply air from the second chuck. In order to prevent air from blowing out through the second sensing hole 144 when loading the second fixture, while allowing vacuum to flow through to achieve vacuum adsorption detection, a first valve is arranged in the second sensing hole. On the lower side of the first valve, a third air supply channel 133 is provided, which is also as shown Fig.11a The second vacuum sensing channel is connected to the other side of the first valve. When the valve is closed, no air can be blown into the second sensing channel.

[0069] Before loading the fixture, the third and fourth chucks must be opened. Compressed air is therefore required to open the chucks. Compressed air is supplied into the third air supply channel 133 through the second sensing hole 144. At this time, the first valve 60 is automatically closed so that the supplied air flows directly to the third and fourth chucks instead of flowing to the adsorption area through the second valve. The fixture can then be clamped into these two chucks, and the air supply is stopped to close the chucks.

[0070] When the fixture is clamped to the second tray by the third chuck and the fourth chuck, vacuum can be started for suction. Since the air supply is stopped, the first valve is automatically opened. During the suction process, the second sensing hole 144 and the third air supply channel 133 are used to sense the vacuum because they are connected to the second vacuum sensing channel through the first valve.

[0071] Fig.16a , 16b 16c takes the first clamp as an example to show how the suction area on the clamp can be selected. However, this design is also applicable to the second clamp. Fig.16a As shown, a plurality of first clamp sealing grooves 25 are provided. In this example, the sealing grooves are arranged in rows and columns in a regular manner. However, the sealing grooves may also be arranged in an irregular manner or in a circular manner. Fig.16b The situation when all four adsorption areas should be activated is shown. To achieve this, a first sealing element 26 is inserted into a sealing groove around the adsorption area. Fig.16c The case where two adsorption regions should be selected is shown. Therefore, the first sealing element is inserted around the two adsorption regions and covers the other adsorption region.

[0072] List of reference numerals

[0073] 1 First clamping system

[0074] 2 Workpiece

[0075] 10 First Chuck

[0076] 11b, 11c, 11d Y reference element on the first chuck

[0077] 12a, 12b, 12c, 12d X reference element on the first chuck

[0078] 13a, 13b Z reference element on the first chuck

[0079] 20 First fixture

[0080] 21, 22, 23, 24 First fixture suction opening

[0081] 25 First fixture sealing groove

[0082] 26 First clamp sealing element

[0083] 30 First Pallet

[0084] 31a, 31b first pair of slots

[0085] 32 First groove

[0086] 33 Upper part of first tray

[0087] 34 Lower part of first tray

[0088] 35 First injector inlet

[0089] 35a First air outlet

[0090] 35b First Cover

[0091] 36 First tray adsorption opening

[0092] 37a, 37b, 37c, 37d X reference element on first pallet

[0093] 38a, 38b, 38c, 38d, 38e, 38f, 38g, 38h Z reference element on the first tray

[0094] 39 First Seal

[0095] 40a, 40b, 40c, 40d Y reference element on the first tray

[0096] 41 Holes for fixing screws

[0097] 42 First Vacuum Ejector

[0098] 42a First injector inlet

[0099] 42b First ejector outlet

[0100] 42c First ejector adsorption opening

[0101] 43 First air inlet

[0102] 44 First vacuum connection hole

[0103] 45 First vacuum hole

[0104] 46 First air channel

[0105] 47a First vacuum suction channel

[0106] 47b First vacuum sensing channel

[0107] 48 First Stopper

[0108] 49 First sensor hole

[0109] 50 Tie rod

[0110] 60 First valve

[0111] 70 Liquid Chamber

[0112] 71 Second valve

[0113] 100 second clamping system

[0114] 110 Second Chuck

[0115] 111Y reference element on the second chuck

[0116] 112 X reference element on the second chuck

[0117] 113 Z reference element on the second chuck

[0118] 120 Second clamp

[0119] 121, 122, 123, 124 second fixture suction opening

[0120] 125 Second fixture sealing groove

[0121] 130 Second Pallet

[0122] 131 Second pallet clamp pair

[0123] 132 Bottom of the second tray

[0124] 133 Third air supply channel

[0125] 135 Second injector inlet

[0126] 135a Second air outlet

[0127] 135b Second cover

[0128] 136 Second tray adsorption opening

[0129] 137 Y reference element on the second pallet

[0130] 138 X reference element on the second pallet

[0131] 140 Z reference element on the second pallet

[0132] 141a The third chuck for clamping

[0133] 141b Fourth chuck for clamping

[0134] 142 Second Vacuum Ejector

[0135] 142a Second injector inlet

[0136] 142b Second ejector outlet

[0137] 142c Second ejector adsorption opening

[0138] 143 Second air inlet

[0139] 144 Second sensor hole

[0140] 145 Second vacuum channel

[0141] 146 Second air channel

[0142] 147 Second vacuum sensing channel

[0143] 148 Second plug

[0144] 150 clamping mechanism

[0145] 151 Second vacuum connection hole.

Claims

1. A clamping system, comprising a chuck (10, 110) and a tray (30, 130) for mounting an object (2, 20) thereon, wherein: The chuck comprises a plurality of chuck reference elements (12a, 12b, 12c, 12d, 11b, 11c, 11d, 13a, 13b) in X, Y and Z directions, wherein the pallet comprises a plurality of pallet reference elements (37a, 37b, 37c, 37d, 139, 40a, 40b, 40c, 40d, 137, 38a, 38b, 38c, 38d, 140) in X, Y and Z directions, wherein a pallet locking mechanism is provided on the pallet and a chuck locking mechanism is provided on the chuck, wherein the pallet can be clamped to the chuck by interaction of the pallet locking mechanism with the chuck locking mechanism, wherein when the pallet is clamped to the chuck, the pallet reference elements are aligned with the chuck reference elements in X, Y and Z directions, Features The tray comprises a vacuum ejector (42, 142) for generating vacuum and a tray suction opening (36, 136) connected in communication with the vacuum ejector for keeping the object positioned on the tray by the generated vacuum.

2. The clamping system according to claim 1, wherein the pallet is provided with a groove arranged inside the pallet for arranging the vacuum ejector therein, and in particular, the elongated direction of the groove is parallel to the top surface of the pallet.

3. A clamping system according to claim 1 or 2, wherein the pallet is provided with an air inlet (43, 143) for supplying pressurized air into the vacuum ejector, and the air inlet is arranged in such a way that when the pallet is clamped with the chuck, the pressurized air supplied into the chuck automatically enters the air inlet.

4. The clamping system according to claim 3, wherein the air inlet is arranged on the bottom surface of the pallet, the air supply outlet is arranged on the top surface of the chuck, and when the pallet is clamped with the chuck, the air inlet of the pallet is automatically aligned with the air supply outlet of the chuck.

5. The clamping system according to claim 1, wherein the tray suction opening is covered by a filter, in particular the filter is a mesh filter.

6. A clamping system according to any one of claims 1 to 5, wherein a pallet sensor mechanism is integrated in the pallet and a chuck sensor mechanism is integrated in the chuck, wherein the pallet sensor mechanism and the chuck sensor mechanism are configured to automatically align when the pallet is clamped with the chuck, in particular the pallet sensor mechanism and the chuck sensor mechanism are suitable for monitoring the vacuum generated by the vacuum ejector.

7. The clamping system according to claim 6, wherein the pallet sensing mechanism comprises a pallet sensing hole (49, 144) arranged on the bottom surface of the pallet (30, 130) and connected to the pallet adsorption opening (36, 136), in particular, the sensing hole is connected to the pallet adsorption opening via a vacuum sensing channel (47b, 147) and a vacuum connecting hole (44, 151).

8. The clamping system according to any one of claims 1 to 7, wherein: An ejector inlet (35, 135) connected to the groove is provided on the surface of the tray for inserting a vacuum ejector into the groove arranged inside the tray, and the ejector can be covered by a cover (35b, 135b) on which an air outlet (35a, 135a) is formed.

9. The clamping system according to any one of claims 1 to 8, wherein: The clamping system also includes a clamp (20, 120) for being mounted on a pallet to hold a workpiece on the pallet, wherein the clamp has at least one clamp suction opening (21, 22, 23, 24, 121, 122, 123, 124), and when the clamp is mounted on the pallet, the clamp suction opening is connected to the pallet suction opening.

10. The clamping system according to claim 9, wherein the clamp comprises at least two clamp suction openings for providing at least two clamp suction areas and a plurality of sealing grooves (25), wherein a clamp sealing element (26) can be inserted into the clamp sealing groove for selectively activating the clamp suction area.

11. The clamping system according to any one of claims 1 to 10, wherein: A liquid chamber (70) is arranged below the tray adsorption opening (36, 136) for storing liquid entering from the tray adsorption opening.

12. The clamping system of claim 11, wherein: The second valve (71) is installed at one end of the liquid chamber to close or open the liquid chamber.

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