Template printing machine

Abstract

The utility model provides a stencil printing machine which is used for printing assembly materials on an electronic substrate. A stencil printer includes a frame, a printhead gantry, and a transfer device. The print head gantry is movably coupled to the frame in a first direction. The transfer device is supported by the printing head door frame and comprises a transfer tray, a first direction air cylinder and a second direction driving device, the first direction air cylinder comprises a cylinder barrel and a piston rod, the piston rod of the first direction air cylinder has a free moving state relative to the cylinder barrel of the first direction air cylinder, and the piston rod of the first direction air cylinder is connected to the transfer tray. A cylinder barrel of the first directional cylinder is coupled to the second directional drive.

Description

Technical Field

[0001] This application generally relates to a stencil printing machine for printing assembly materials (e.g., adhesive substances) onto an electronic substrate, such as solder paste, and the electronic substrate may be a printed circuit board. Background Technology

[0002] In a typical circuit board manufacturing process, a stencil printer is used to print solder paste onto the circuit board. A circuit board, broadly known as an electronic substrate, has pads on which solder paste can be deposited, each pad bearing a specific pattern. The stencil of the printer has multiple holes that match the pattern on the circuit board. Once the circuit board is automatically fed into the stencil printer and aligned with the stencil, it is lifted by a substrate support and fixed relative to the adjacent stencil. Solder paste is then dispensed by a squeegee moving across the stencil, allowing it to pass through the holes in the stencil and onto the circuit board. After the printing operation is complete, the circuit board is released, lowered, and detached from the stencil, then transported to another location within the printed circuit board production line.

[0003] When the holes on the stencil become clogged, the old stencil needs to be removed and replaced with a clean one. Stencils typically need to be replaced periodically. Furthermore, when changing the circuit board to be printed on, the pattern on the board changes, requiring the old stencil to be removed and replaced with a new stencil that matches the pattern on the circuit board. The old stencil to be removed often has undistributed solder paste buildup, resulting in incomplete solder paste utilization. Utility Model Content

[0004] Through long-term observation and research, the inventors of this application have found that existing stencil printing machines used to transfer solder paste on stencils have difficulty simultaneously achieving cost control, system complexity control, and space reduction.

[0005] To at least partially solve the above-mentioned technical problems, this application provides a stencil printing machine for printing assembly materials on an electronic substrate. The stencil printing machine includes a frame, a printhead gantry, and a transfer device. The printhead gantry is movably connected to the frame along a first direction. The transfer device is supported by the printhead gantry and includes a transfer tray, a first-direction cylinder, and a second-direction drive device. The first-direction cylinder includes a cylinder barrel and a piston rod. The piston rod of the first-direction cylinder has a free-moving state relative to its cylinder barrel. The piston rod of the first-direction cylinder is connected to the transfer tray, and the cylinder barrel of the first-direction cylinder is connected to the second-direction drive device.

[0006] In some embodiments, the first directional cylinder further includes a piston disposed in its cylinder barrel. The cylinder barrel of the first directional cylinder is provided with a first port and a second port located on opposite sides of the piston, and the first port and the second port are controllably connected to a compressed gas source.

[0007] In some embodiments, the second direction drive device includes a second direction cylinder and a second direction auxiliary cylinder, wherein the second direction cylinder is configured to drive the second direction auxiliary cylinder to drive the first direction cylinder and the transfer tray to move along the second direction.

[0008] In some embodiments, the second directional cylinder includes a fixed portion and a movable portion. The fixed portion of the second directional cylinder is connected to the printing head gantry, and the movable portion of the second directional cylinder is connected to the cylinder barrel of the first directional cylinder. The second directional auxiliary cylinder includes a fixed portion and a movable portion. The fixed portion of the second directional auxiliary cylinder is connected to the piston rod of the first directional cylinder, and the transfer tray is connected to the movable portion of the second directional auxiliary cylinder.

[0009] In some embodiments, the stroke of the second directional auxiliary cylinder is less than the stroke of the second directional cylinder.

[0010] In some embodiments, the stencil printing machine further includes a retaining device comprising a retainer and a retaining clamp. The retainer is supported by a frame and is extendable and retractable in a third direction. The retaining clamp is coupled to a transfer tray and is closable and openable to releasably hold the retainer.

[0011] In some embodiments, the retaining clamp includes pneumatic grippers.

[0012] In some embodiments, the retainer includes a retaining piece extending along a first direction and having a certain length.

[0013] In some embodiments, the retaining device further includes a third-party directional cylinder that is droopingly connected to the retainer.

[0014] In some embodiments, the retaining device includes two retainers and two retaining clips, the two retainers being located on opposite sides of the transfer tray in a third-order direction, and the two retaining clips cooperating with the two retainers respectively.

[0015] The "first direction" mentioned above refers to the Y direction of the template printing machine.

[0016] The "second direction" mentioned above refers to the Z direction of the template printing machine.

[0017] The aforementioned "third direction" refers to the X direction of the template printing machine.

[0018] This application uses a first-direction cylinder to change the position of the transfer tray in the first direction (Y direction), and the transfer tray, the first-direction cylinder, and its second-direction drive device (Z direction) are all supported by the printhead gantry. The first-direction cylinder is configured to allow the squeegee assembly to move relative to the transfer tray in the first direction while the transfer tray is held stationary relative to the template. This not only enables solder paste transfer operations through the cooperation of the transfer tray and the squeegee, but also eliminates the need for expensive motors and linkage control systems. Furthermore, when not performing solder paste transfer operations, the transfer tray is raised to the side of the squeegee in the first direction, thus minimizing the space occupied by the transfer device under the printhead gantry. Attached Figure Description

[0019] Figure 1 This is a perspective view of a template printing machine according to an embodiment of this application;

[0020] Figure 2A yes Figure 1 A perspective view of a portion of a component of the template printing machine shown;

[0021] Figure 2B yes Figure 2A A perspective view of another part of the template printing machine shown;

[0022] Figure 2C yes Figure 2A A side view of a portion of the template printing machine shown;

[0023] Figure 3A yes Figure 2A A perspective view of the transfer device shown;

[0024] Figure 3B yes Figure 2A A perspective view of the transfer device shown from another angle;

[0025] Figure 3C yes Figure 2A A side view of the transfer device in its first state;

[0026] Figure 3D yes Figure 2A A side view of the transfer device in its second state;

[0027] Figure 3E yes Figure 3A The side view of the first-direction cylinder shown;

[0028] Figure 4A-4S This is a simplified schematic diagram illustrating the first illustrative operation process of the template printing machine of this application performing the assembly material transfer operation;

[0029] Figures 5A-5B This is a simplified schematic diagram illustrating a second illustrative operation process of the template printing machine of this application performing the assembly material transfer operation;

[0030] Figure 6 This is a simplified schematic diagram showing the working state of the template printing machine of this application performing the assembly material collection operation.

[0031] Main Identification

[0032] Template printing machine 100; frame 110; printhead gantry 115; drive motor 118; printhead assembly 120; squeegee assembly 125; transfer device 130; holding device 140; template 150; replaceable template 150'; substrate conveying device 160; substrate support device 165; substrate lifting device 170; control device 180; first squeegee 212; second squeegee 214; motor assembly 220; first motor 222; second motor 224; first direction cylinder 231; second direction cylinder 232; second direction auxiliary cylinder 234; transfer tray 235; holding clamp 242; holding member 243; third Directional drive device 245; movable part 246 (of the third directional cylinder); fixed part 247 (of the third directional cylinder); frame 252; template body 255; cylinder barrel 312 (of the first directional cylinder); piston rod 314 (of the first directional cylinder); first port 315; second port 317; piston 318; fixed part 322 (of the second directional cylinder); movable part 324 (of the second directional cylinder); fixed part 342 (of the second directional auxiliary cylinder); movable part 344 (of the second directional auxiliary cylinder); first connector 350; second connector 360; third connector 370; compressed gas source 390. Detailed Implementation

[0033] Various specific embodiments of this application will now be described with reference to the accompanying drawings, which form part of this specification. It should be understood that although directional terms such as "front," "rear," "upper," "lower," "left," "right," "top," and "bottom" are used in this application to describe various exemplary structural parts and elements, their use is merely for illustrative purposes and is based on the exemplary orientations shown in the accompanying drawings. Since the embodiments disclosed in this application can be arranged in different orientations, these directional terms are for illustrative purposes only and should not be considered as limiting.

[0034] Figure 1 This is a perspective view of a stencil printing machine according to an embodiment of the present application, showing the overall structure of a stencil printing machine 100 according to an embodiment of the present application. Figure 1As shown, the stencil printing machine 100 includes a frame 110 for supporting the components of the stencil printing machine. The components of the stencil printing machine include a printhead assembly 120, a printhead gantry (or printhead support device) 115, a stencil 150, a substrate transport device 160, a substrate support device 165, a substrate lifting device 170, a drive motor 118, and a control device 180. The stencil 150 has a plurality of holes forming a pattern that corresponds to the pattern formed by the positions of the assembly material (e.g., solder paste) to be distributed on the substrate to be printed. The stencil printing machine 100 includes a Y direction (first direction), a Z direction (second direction), and an X direction (third direction). Figure 1 In orientation, the Y direction is the forward and backward direction, the Z direction is the up and down direction, and the X direction is the left and right direction.

[0035] Still as Figure 1 As shown, in the Z direction, the printhead assembly 120 is located above the template 150, the substrate transport device 160 is located below the template 150, and the substrate lifting device 170 is located below the substrate transport device 160. The printhead gantry 115 is supported by the frame 110 and is movable in the Y direction under the drive of the drive motor 118. The printhead assembly 120 is supported by the printhead gantry 115 and can move with the printhead gantry 115 in the Y direction. The printhead assembly 120 includes a squeegee assembly 125, which is movable in the Z direction, so that when the squeegee assembly 125 is lowered to the engagement template 150, pressure can be applied to the assembly material (e.g., solder paste) dispensed on the template 150, forcing it through holes in the template 150 to be deposited onto the substrate located below the template 150. The substrate transport device 160 is, for example, a transport track that transports the substrate below the template 150 in the X direction. A substrate support device 165 is provided on or near the substrate conveying device 160. A substrate lifting device 170 is used to lift the substrate support device 165 so that the substrate supported on it reaches the printing position close to the template 150. A control device 180 is used to control the above operations of the template printing machine 100.

[0036] A stencil printing machine 100 according to one embodiment of this application further includes a transfer device 130 and a holding device 140. When the stencil 150 needs to be replaced, the stencil 150 is first removed and then replaced with a new stencil. The transfer device 130 can cooperate with the squeegee assembly 125 to transfer solder paste on the stencil 150 to a replacement stencil, so as to reuse residual solder paste on the stencil 150. The holding device 140 is used to hold the transfer tray (i.e., such as) of the transfer device 130 before the transfer device 130 cooperates with the squeegee assembly 125. Figure 2AThe transfer tray 235 shown is held stationary relative to the template 150. The transfer device 130 of this application can also cooperate with the squeegee assembly 125 to collect solder paste dripping from the suspended squeegee assembly 125 when the squeegee assembly 125 is paused due to the need to replace the solder paste container (not shown) of the template printing machine 100. The specific structure of the transfer device 130 and the holding device 140 will be described in conjunction with... Figure 2A-3C Detailed introduction.

[0037] Figure 2A-2C The specific structure of a portion of the components of the template printing machine 100 is shown, wherein, Figure 2A A first-person perspective (front to back) perspective view of these components is shown. Figure 2B A second-view (rear-to-front) perspective perspective of these components is shown, while Figure 2C A side view of these components is shown. Figures 2A to 2C The template printing machine 100 shown includes a portion of a printhead gantry 115, a printhead assembly 120, a transfer device 130, a holding device 140, and a template 150. The printhead assembly 120 and the transfer device 130 are both supported by the printhead gantry 115. Part of the holding device 140 is supported by the printhead gantry 115, and the other part is supported by… Figure 1 The framework 110 supports it.

[0038] like Figure 2A As shown, the template 150 includes a frame 252 and a template body 255, with the frame 252 surrounding the template body 255. The template body 255 is generally plate-shaped and has multiple openings or holes (not shown in the figure) for allowing solder paste to pass through the template 150 and be deposited onto the substrate below the template 150. The frame 252 has a certain height in the Z direction.

[0039] like Figure 2A-2CAs shown, the printhead assembly 120 includes a doctor blade assembly 125 and a motor assembly 220 for driving the doctor blade assembly 125 to move along the Z direction. The doctor blade assembly 125 includes a first doctor blade 212 and a second doctor blade 214 arranged side by side along the Y direction, with the first doctor blade 212 located in front of the second doctor blade 214. The motor assembly 220 includes a first motor 222 and a second motor 224, which are used to drive the first doctor blade 212 and the second doctor blade 214 respectively, so that the first doctor blade 212 and the second doctor blade 214 can move toward and away from the template 150 respectively, thereby being able to engage with the template 150 and separate from the template 150. The blades (not shown) of the first doctor blade 212 and the second doctor blade 214 extend along the X direction and are inclined relative to the template 150, with the inclination directions of the two doctor blades being opposite. Therefore, the first scraper 212 can be selected to scrape the solder paste on the stencil 150 in a first direction along the Y direction (e.g., backward), or the second scraper 214 can be selected to scrape the solder paste on the stencil 150 in a second direction along the Y direction (e.g., forward). As previously stated... Figure 1 As described, the movement of the scraper assembly 125 in the Y direction is driven by the drive motor 118.

[0040] Continue as Figure 2A-2C As shown, the transfer device includes a transfer tray 235, two first-direction cylinders 231, and a second-direction drive device. The second-direction drive device includes a second-direction cylinder 232 and two second-direction auxiliary cylinders 234, which will... Figures 3A-3C More details are shown below.

[0041] The transfer tray 235 includes a flat, disc-shaped structure extending generally along the X direction. The transfer tray 235 includes a raised position and a lowered position, and is capable of moving toward and away from the template 150 under the drive of a second-direction drive device to switch between the raised and lowered positions. When the transfer tray 235 is in its raised position (e.g., ...), Figure 2C When the transfer tray 235 is in its lowered position, it is raised relative to the stencil 150 and positioned on one side of the squeegee assembly 125 in the Y direction, thus not affecting the squeegee assembly 125's scraping of the stencil 150 (i.e., performing the printing operation). When the transfer tray 235 is in its lowered position, it is lowered to contact the stencil 150, i.e., positioned on the stencil 150. Therefore, the transfer tray 235 can cooperate with the squeegee assembly 125 to transfer solder paste from the stencil 150.

[0042] The retaining device 140 includes a retaining clip 242, a retaining member 243, and a third-direction drive device 245. The retaining clip 242 can releasably clamp the retaining member 243, which can be driven by the third-direction drive device 245 to extend and retract in the X direction, and in its extended position, it extends into the retaining clip 242 and can be clamped by the retaining clip 242. In the embodiment shown in the figure, there are two retaining members 243, which are arranged on opposite sides of the transfer tray 235 in the X direction. For this purpose, there are also two retaining clips 242, each cooperating with one of the two retaining members 243. In other embodiments, there may be only one or more retaining clips and retaining members.

[0043] The retaining clamp 242 is, for example, a pneumatic gripper that can be opened and closed. The retaining clamp 242 is supported by the printhead gantry 115 and connected to the transfer tray 235.

[0044] Retainer 243 is made of frame 110 (see Figure 1 Support. The retainer 243 includes an elongated retaining piece extending a certain length along the Y direction. In some embodiments, the third-party directional drive device 245 is a third-party directional cylinder, which includes a fixed portion 247 and a movable portion 246 (see...). Figure 2A The retainer 243 is connected to the movable part 246 of the third-party directional cylinder, while the fixed part 247 of the third-party directional cylinder is connected to the frame 110 (see...). Figure 1 Thus, retainer 243 is supported on frame 110 by a third-direction cylinder and can extend toward retainer 242 in the X direction or retract away from retainer 242. The number of third-direction cylinders can be multiple as shown in the figure, or it can be a single cylinder.

[0045] After the transfer tray 235 descends to the lowered position, the retaining member 243 of the retaining device 140 is extended to its extended position by a third-party directional cylinder and is received and clamped by the retaining clamp 242. Since the retaining member 243 is supported by the frame 110 (see...), Figure 1 The retainer 243 provides support, thus limiting the movement of the transfer tray 235 in the Y direction and also limiting its movement in the Z direction, thereby keeping the transfer tray 235 stationary relative to the template 150. When the transfer tray 235 is stationary relative to the template 150, the transfer of solder paste can be performed by moving the scraper assembly 125 relative to the transfer tray 235 in the Y direction.

[0046] Figures 3A-3E The specific structure of the transfer device 130 is shown more clearly, wherein, Figure 3A This is a perspective view (from front to back) of the transfer device 130. Figure 3BThis is a perspective view (from back to front) of the transfer device 130. Figure 3C This is a side view of the transfer device 130 in its first state. Figure 3D This is a side view of the transfer device 130 in its second state. Figure 3E yes Figure 3A The side view of the first directional cylinder 231 shown.

[0047] like Figure 3A As shown, the transfer tray 235 of the transfer device 130 is generally flat, extending a certain length along the X direction and a certain width along the Y direction. The second directional cylinder 232 includes a fixed portion 322 and a movable portion 324. In the embodiment shown, the second directional cylinder 232 is a rodless cylinder, with the fixed portion 322 being a cylinder barrel and the movable portion 324 being a slider. The second directional cylinder 232 drives the component to move by the movement of the slider along the Z direction. The second directional auxiliary cylinder 234 includes a fixed portion 342 and a movable portion 344. In the embodiment shown, the second directional auxiliary cylinder 234 is a standard cylinder, with the fixed portion 342 being a cylinder barrel and the movable portion 344 being a piston rod. The second directional auxiliary cylinder 234 drives the component to move by the extension and retraction of the piston rod along the Z direction. In other embodiments, the second directional cylinder 232 and the second directional auxiliary cylinder 234 may also be other types of cylinders. The stroke of the second-direction auxiliary cylinder 234 is less than the stroke of the second-direction cylinder 232. That is, the maximum distance that the second-direction auxiliary cylinder 234 drives the component to move is less than the maximum distance that the second-direction cylinder 232 drives the component to move.

[0048] It should be noted that the fixed part and movable part of the cylinder mentioned in this application are relative to each other. That is, the fixed part of the cylinder is fixed relative to its movable part, and the movable part of the cylinder is movable relative to its fixed part.

[0049] like Figure 3B and 3E As shown, the first directional cylinder 231 is a double-acting cylinder, which includes a cylinder barrel 312 and a piston rod 314. A piston 318 is located within the cylinder barrel 312 of the first directional cylinder 231. Figure 3EThe first port 315 and the second port 317 (shown by dashed lines) are located on opposite sides and are used for controllable communication with a compressed gas source 390, allowing compressed gas to be input to and output from the cylinder 312. For example, by controlling the input of compressed gas to the first port 315 and the second port 317, the piston rod 314 can be extended and retracted, and the piston rod 314 can be in a free-moving state relative to the cylinder 312. For example, allowing compressed gas to enter the first port 315 can push the piston rod 314 to extend, while allowing compressed gas to enter the second port 317 can retract the piston rod 314. Furthermore, if compressed gas is not allowed to enter either the first port 315 or the second port 317 (i.e., no compressed gas is input into the cylinder 312), the piston rod 314 can be in a free-moving state relative to the cylinder 312. When the piston rod 314 is in a free-moving state, the piston rod 314 and the cylinder 312 are relatively free. The movement of the piston rod 314 within a certain range in the first direction does not cause the cylinder 312 to move, and the movement of the cylinder 312 within a certain range in the first direction does not cause the cylinder 312 to move.

[0050] Figure 3C and 3D The two states of the transfer device 130 are shown respectively. Figure 3C In the state shown, the movable parts or piston rods of each cylinder do not move, while... Figure 3D In the described state, the movable parts or piston rods of each cylinder have moved a certain distance. For example... Figures 3A-3D As shown, the transfer device 130 also includes a first connector 350, a second connector 360, and a third connector 370. The transfer tray 235 is connected to the movable portion 344 of the second-direction auxiliary cylinder 234 via the first connector 350. The fixed portion 342 of the second-direction auxiliary cylinder 234 is connected to the piston rod 314 of the first-direction cylinder 231 via the second connector 360. The cylinder barrel 312 of the first-direction cylinder 231 is connected to the movable portion 324 of the second-direction cylinder 232 via the third connector 370. The fixed portion 322 of the second-direction cylinder 232 is connected to the printing head gantry 115 (see...). Figure 2A-2C ).

[0051] In addition, the retaining clip 242 is connected to the second connector 360, so the retaining clip 242 is connected to the transfer tray 235 via the second connector 360 and the second-direction additional cylinder 234.

[0052] First directional cylinder 231, second directional cylinder 232, second directional auxiliary cylinder 234, third directional drive device (third directional cylinder, such as...) Figure 2A As shown) 245 and retaining clip 242 are both made of Figure 1 The control device 180 in the middle is used for control.

[0053] See Figure 2C and 3D Since the transfer device 130 is connected to the printhead gantry 115 via the fixing part 322 of the second directional cylinder 232, the printhead gantry 115 supports the transfer device 130. A second directional drive device, including the second directional cylinder 232 and the second directional auxiliary cylinder 234, drives the transfer tray 235 to rise and fall along the Z direction, thereby switching the transfer tray 235 between its raised and lowered positions. Specifically, the second directional cylinder 232 drives the first directional cylinder 231, the second directional auxiliary cylinder 234, and the transfer tray 235 to move together along the Z direction.

[0054] Furthermore, the first directional cylinder 231 allows the transfer tray 235 to cooperate with the squeegee assembly 125 to perform solder paste transfer operations. When the transfer tray 235 is moved along the Z direction to its lowered position and contacts the template 150, and is held stationary relative to the template 150 by, for example, the holding device 140, the first directional cylinder 231 allows the printhead gantry 115 to move along the Y direction toward and away from the transfer tray 235 by allowing the piston rod 314 of the first directional cylinder 231 to be in a free-moving state. This is because, although the piston rod 314 of the first directional cylinder 231 is held together with the transfer tray 235 and cannot move along the Y direction due to being connected to the transfer tray 235 by the second directional auxiliary cylinder 234, the cylinder barrel 312 of the first directional cylinder 231 and the piston rod 314 are free-moving relative to each other, therefore, the cylinder barrel 312 of the first directional cylinder 231 can move together with the printhead gantry 115. Therefore, the first directional cylinder 231 will not prevent the printhead gantry 115 from driving the scraper assembly 125 to move toward and away from the transfer tray 235 in the Y direction.

[0055] It is worth noting that although the second directional drive device in the embodiment shown in the figure includes two stages of cylinders, namely a second directional cylinder and a second directional auxiliary cylinder, in other embodiments, the second directional cylinder may also include only one stage of cylinders (e.g., only the second directional cylinder). Furthermore, although the transfer device in the embodiment shown in the figure includes two first directional cylinders, one second directional cylinder, and two second directional auxiliary cylinders, in other embodiments, the number of each cylinder may be more or less, and is not limited to the number shown in the embodiment.

[0056] Figure 4A-4S This is a simplified schematic diagram illustrating the first illustrative operation process (hereinafter referred to as "solder paste (or assembly material) transfer process") of the stencil printing machine 100 in transferring solder paste from the stencil to be removed 150 to a replacement stencil. Figure 4A-4SThe solder paste transfer process shown is suitable for cases where the stencil body 255 of the stencil 150 is relatively thin, such as stencils used for printing substrates in the semiconductor industry. Compared to stencils used for printing substrates in other industries (such as consumer electronics), the stencils used for printing semiconductor substrates are thinner to allow for precise control of the amount of solder paste. Figure 4A-4S In the embodiment shown, during the process of transferring solder paste on the template 150 by the transfer device, a holding device located above the template 150 is used to hold the transfer tray 235 on the template 150 so that it is stationary relative to the template 150. In addition to limiting the movement of the transfer tray 235 relative to the template 150 in the Y and Z directions, it can also reduce the force applied to the template 150 by the second direction drive device along the Z direction through the transfer tray 235, thus protecting the template 150 from damage.

[0057] Figure 4A-4S The solder paste transfer process shown includes four stages. The first stage is as follows: Figure 4A-4I The diagram illustrates the process of transferring solder paste from the stencil 150 to be removed onto the transfer tray 235. The second stage is as follows... Figure 4J As shown, this is the process of replacing the template 150 to be removed with a new, replaced template 150'. The third stage is as follows... Figure 4K-4O The diagram illustrates the process of transferring solder paste from transfer tray 235 to a replacement stencil 150'. The fourth stage is as follows... Figure 4P-4S The diagram shows the process of resetting the transfer tray 235 to its raised position.

[0058] The first stage of the solder paste transfer process is as follows:

[0059] Figure 4A The initial state of each component at the start of the solder paste transfer process is shown. In this state, the transfer tray 235 is in its raised position and has not yet moved in the Z direction (second direction, up and down in the figure) and Y direction (first direction, left and right in the figure). The first scraper 212 and the second scraper 214 of the scraper assembly are also in their raised positions. The solder paste S to be transferred on the template 150 to be removed is located below the scraper assembly. The solder paste S to be transferred is elongated in the X direction (third direction, front and back direction perpendicular to the paper in the figure). Furthermore, the piston rod 314 of the first direction cylinder 231 is held in the retracted state (e.g., by...). Figure 3E Compressed gas is input into the second port 317 of the first directional cylinder 231 shown.

[0060] Subsequently, the second-direction auxiliary cylinder 234 drives the transfer tray 235 to move downwards until the movable part (piston rod) 344 of the second-direction auxiliary cylinder 234 moves to the end of its extended stroke, reaching the position shown in the image. Figure 4BThe position shown. Next, the second directional cylinder 232 drives the transfer tray 235 to continue moving downwards until the transfer tray 235 contacts the upper surface of the template 150, at which point the transfer tray 235 reaches its lowered position, as indicated. Figure 4C As shown. In this position, hold clip 242 ( Figure 4C (Not visible in the middle) along the X direction (third direction) and retainer 243 ( Figure 4C (Invisible in the middle) Alignment.

[0061] Next, as Figure 4D As shown, the third-party directional drive device (third-party directional cylinder) 245 drives the retainer 243 to extend in the X direction and into the retaining clamp 242, which is in the open state. The retaining clamp 242 then closes, clamping the retainer 243. Thus, the retainer 243 holds the transfer tray 235 stationary relative to the template.

[0062] Next, as Figure 4E As shown, the first scraper 212 is moved downwards to contact the upper surface of the template 150. Then, the piston rod 314 of the first directional cylinder 231 is in a free-moving state, and the printing head gantry 115 moves to the left along the Y direction toward the transfer tray 235, thereby causing the first scraper 212, the second scraper 214, the second directional cylinder 232, and the cylinder barrel 312 of the first directional cylinder 231, which are supported by it, to also move to the left. Due to the retaining clamp 242 and the retainer 243 (see... Figure 4D The retainer 243 is connected to the frame 110 (not shown in the figure), and the retaining clip 242 is connected to the second connector 360 (as shown in the figure). Figure 3A The first directional cylinder 231 is connected to the second directional auxiliary cylinder 234. Therefore, during the leftward movement of the printing head gantry 115 in the Y direction, the second directional auxiliary cylinder 234 and the transfer tray 235 connected to it remain stationary. Furthermore, since the piston rod 314 of the first directional cylinder 231 is connected to the second directional auxiliary cylinder 234, the piston rod 314 of the first directional cylinder 231 also remains stationary. However, since the piston rod 314 of the first directional cylinder 231 is in a free-moving state relative to its cylinder 312, during the leftward movement of the printing head gantry 115 in the Y direction, the cylinder 312 of the first directional cylinder 231 can move to the left relative to its piston rod 314. Therefore, the piston rod 314 gradually extends relative to the cylinder 312, as... Figure 4F As shown. During this process, the first scraper 212 scrapes the solder paste S on the template 150 onto the transfer tray 235.

[0063] Next, as Figure 4G As shown, the first scraper 212 is moved upwards away from the template 150. Then, as... Figure 4HAs shown, the retaining clamp 242 is opened, releasing the retainer 243, and the retainer 243 is retracted in the X direction by the third-party directional drive device (third-party directional cylinder) 245. Thus, the retainer 243 no longer holds the transfer tray 235.

[0064] The second stage of the solder paste transfer process is as follows:

[0065] like Figure 4I As shown, the piston rod 314 of the first directional cylinder 231 is first kept in the extended state (e.g., by moving it towards the cylinder). Figure 3E Compressed gas is input into the first port 315 of the first directional cylinder 231, and then the transfer tray 235 is driven upward by the second directional auxiliary cylinder 234 and the second directional cylinder 232, thereby moving the transfer tray 235 to a position close to the first scraper 212 and the second scraper 214. In this position, the transfer tray 235 can collect the solder paste dripping from the first scraper 212.

[0066] Next, as Figure 4J As shown, remove template 150 and replace it with a new replacement template 150'.

[0067] The third stage of the solder paste transfer process is as follows:

[0068] like Figure 4K and 4L As shown, the transfer tray 235 is driven downward by the second directional cylinder 232 and the second directional auxiliary cylinder 234, so that it reaches the lowered position. Figure 4L (as shown in the image). Then, as... Figure 4M As shown, the retainer 243 is again driven to extend in the X direction by the third-party directional drive device (third-party directional cylinder) 245 and enter the retaining clamp 242, which is in the open state. The retaining clamp 242 then closes, clamping the retainer 243. Thus, the retainer 243 once again holds the transfer tray 235 on the replacement template 150'.

[0069] Then as Figure 4NAs shown, the second scraper 214 is moved downwards to contact the upper surface of the replacement template 150'. Then, the piston rod 314 of the first directional cylinder 231 is in a free-moving state, and the printing head gantry 115 moves to the right along the Y direction, thereby causing the first scraper 212, the second scraper 214, the second directional cylinder 232, and the cylinder barrel 312 of the first directional cylinder 231, which it supports, to also move to the right, while the second directional auxiliary cylinder 234 and the transfer tray 235 connected to it remain stationary. Furthermore, since the piston rod 314 of the first directional cylinder 231 is in a free-moving state, during the movement of the printing head gantry 115 to the right along the Y direction, the cylinder barrel 312 of the first directional cylinder 231 moves to the right relative to the piston rod 314, so the piston rod 314 gradually retracts relative to its cylinder barrel 312, as... Figure 4O As shown. During this process, the second scraper 214 scrapes the solder paste S on the transfer tray 235 onto the replacement template 150'.

[0070] The fourth stage of the solder paste transfer process is as follows:

[0071] like Figure 4P As shown, the second scraper 214 is moved upwards away from the replacement template 150'. Then, as... Figure 4Q As shown, the retaining clamp 242 is opened, releasing the retainer 243, and the retainer 243 is retracted in the X direction by the third-party directional drive device (third-party directional cylinder) 245. Thus, the retainer 243 no longer holds the transfer tray 235.

[0072] Next, as Figure 4R and 4S As shown, the piston rod of the first directional cylinder 231 is first kept in the retracted state (for example, by moving it towards the cylinder). Figure 3E Compressed gas is input into the second port 317 of the first directional cylinder 231 shown. Then, the transfer tray 235 is driven to move upward by the second directional cylinder 232 and the second directional auxiliary cylinder 234, so that it returns to the raised position. Figure 4S (as shown in the image).

[0073] Thus, the first illustrative operation of solder paste transfer is completed.

[0074] In the first illustrative operation of solder paste transfer, when the first scraper 212 scrapes solder paste onto the transfer tray 235 and the second scraper 214 scrapes solder paste away from the transfer tray 235, the piston rod 314 of the first directional cylinder 231 is in a free-moving state. This allows the cylinder 312 of the first directional cylinder 231 to move towards and away from the piston rod 314 in the Y direction while the piston rod 314 remains stationary. Therefore, the first scraper 212 / second scraper 214 can move relative to the transfer tray 235, which remains stationary on the template 150, along with the printing head gantry 115 driven by the drive motor 118, to achieve solder paste transfer. When the transfer tray 235 is raised and lowered, the piston rod 314 of the first directional cylinder 231 is no longer in a free-moving state but remains in an extended or retracted state, thereby stably holding the transfer tray 235 in place by the piston rod 314.

[0075] Figure 5A and 5B This is a simplified schematic diagram illustrating a partial state of a second illustrative operation of the solder paste (or assembly material) transfer process of the stencil printing machine of this application. The second operation process is... Figure 4A-4S The first operating procedure shown is similar, with the main difference being that in the second operating procedure, the transfer tray 235 is held stationary on the template 150 by the cooperation of the substrate lifting device 170 and the substrate support device 165 with the second directional cylinder 232 and the second directional auxiliary cylinder 234. In the first operating procedure, the transfer tray 235 is held stationary on the template 150 by a holding device. The second operating procedure is particularly suitable for printing substrates with a certain thickness (e.g., substrates used in the consumer electronics industry).

[0076] like Figure 5A As shown, the transfer tray 235 is located above the template 150, while the substrate lifting device 170 and the substrate support device 165 are located below the template 150. When it is necessary to keep the transfer tray 235 stationary on the template 150, the transfer tray 235 is lowered to contact the upper surface of the template 150, and the substrate lifting device 170 raises the substrate support device 165 so that it abuts against the lower surface of the template 150, achieving the desired effect. Figure 5B The state shown is such that the transfer tray 235 and the template 150 are clamped between the second-direction auxiliary cylinder 234 and the substrate support device 165, thereby keeping the transfer tray 235 stationary on the template 150. If it is necessary to release the transfer tray 235, the substrate support device 165 is lowered and the transfer tray 235 is raised by the substrate lifting device 170.

[0077] Figure 6This is a simplified schematic diagram illustrating the working state of the stencil printing machine of this application in collecting solder paste dripping from the scraper when changing solder paste containers (hereinafter referred to as "solder paste collection operation"). Figure 6 As shown, when the stencil printer is printing using the first squeegee 212 or the second squeegee 214, if it is necessary to change the solder paste container (not shown in the figure), the first squeegee 212 or the second squeegee 214 that is performing the printing operation needs to be raised. Then, the transfer tray 235 is moved below the first squeegee 212 or the second squeegee 214. For example, the transfer tray 235 is driven downwards by the second directional auxiliary cylinder 234, and subsequently extended to the right below the first squeegee 212 or the second squeegee 214 by the first directional cylinder 231. This allows the transfer tray 235 to collect solder paste dripping from the squeegee.

[0078] In the solder paste transfer operation, the first directional cylinder 231 of this application may not be used as a driving device. In the solder paste collection operation, the first directional cylinder 231 of this application may be used as a driving device.

[0079] The inventors of this application have discovered through long-term observation and research that, in a stencil printing machine, if a transfer tray is to be used in conjunction with a squeegee supported by a printing head gantry to perform a solder paste transfer operation (i.e., to transfer the solder paste from the stencil to be removed to a new stencil), the following conditions must be met: (1) When the transfer tray and the squeegee work together to perform the solder paste transfer operation, the transfer tray must be kept stationary on the stencil so that it cannot move relative to the stencil in the Y and Z directions. In this way, the printing head gantry moving in the Y direction can be used to drive the squeegee to move, and the residual solder paste on the stencil to be removed can be transferred to the transfer tray, and the solder paste can be transferred from the transfer tray to the new stencil; (2) After the solder paste transfer operation is completed, the transfer tray must not affect the squeegee's printing operation. Therefore, when the transfer tray is not in use, it cannot be located on the working path of the squeegee's printing operation, but should be able to be moved in both the Y and Z directions.

[0080] The inventors of this application have also discovered that if the movement of the transfer tray in the Y direction is achieved by a motor, there are two possible configurations for the motor. The first configuration involves mounting the motor on the frame of the stencil printing machine and slidingly connecting it to the transfer tray via a track on the frame. This allows the motor to both restrict the transfer tray's movement in the Y direction during solder paste transfer and to remove the transfer tray after the transfer operation is complete. However, with this first configuration, the motor's control of the transfer tray's movement needs to be linked to the drive motor of the printing head gantry to ensure that the movements of the transfer tray and the squeegee on the printing head gantry do not interfere with each other. This requires the stencil printing machine's control system to have high control precision, making the system complex and costly. Furthermore, with this first configuration, the transfer tray and the track on the frame are always in a sliding connection state. This requires the transfer tray and its second-direction drive device to be relatively wide in the X direction (third direction), while the space under the printing head gantry is very limited. This results in a more congested space under the printing head gantry, which is unfavorable for the arrangement of other components. The second setup involves mounting the motor on the printhead gantry. While this allows the transfer tray to be moved when not in use, it prevents the tray from working in conjunction with the squeegee to transfer solder paste, as the motor, transfer tray, and squeegee move together in the Y-direction. Furthermore, if the transfer tray's Y-direction movement is achieved via a motor, the motor itself is relatively expensive.

[0081] This application uses a first-direction cylinder to change the position of the transfer tray in the first direction (Y direction), and the transfer tray, the first-direction cylinder, and its second-direction drive device (Z direction) are all supported by the printhead gantry. The first-direction cylinder is configured to allow the squeegee assembly to move relative to the transfer tray in the first direction while the transfer tray is held stationary relative to the template. This not only enables solder paste transfer operations through the cooperation of the transfer tray and the squeegee, but also eliminates the need for expensive motors and linkage control systems. Furthermore, when not performing solder paste transfer operations, the transfer tray is raised to the side of the squeegee in the first direction, thus minimizing the space occupied by the transfer device under the printhead gantry.

[0082] Furthermore, the second-direction drive device for the transfer tray in this application includes a two-stage cylinder, namely, a second-direction cylinder and a second-direction auxiliary cylinder. Since the cylinder driving the transfer tray to move in the second direction also provides a holding force on the transfer tray in the Z direction (second direction) when the transfer tray performs solder paste transfer operations, by providing a two-stage cylinder, the working component (e.g., piston rod) of the cylinder (especially the second-direction auxiliary cylinder that directly acts on the transfer tray) can be made shorter, thus preventing deformation of the piston rod when the cylinder provides a holding force on the transfer tray. In addition, by providing a two-stage cylinder, the transfer device of this application can also perform solder paste collection operations (such as…) Figure 6 As shown, the transfer tray can be extended downwards to a certain distance from the scraper and stencil using only the second-direction auxiliary cylinder, without getting too close to either. Since there is a certain thickness of solder paste on the stencil and a curtain-like layer of solder paste on the scraper during the solder paste collection operation, extending the transfer tray downwards using only the second-direction auxiliary cylinder not only prevents the transfer tray from touching the solder paste on the stencil and contaminating its lower surface, but also maximizes the collection of the curtain-like solder paste from the scraper.

[0083] Furthermore, this application provides two methods for holding the transfer tray. The first method is suitable for cases where the stencil body is relatively thin (e.g., stencils used for printing substrates in the semiconductor industry). It utilizes a retractable holding member mounted on a frame and a holding clip connected to the transfer tray to hold the transfer tray stationary relative to the stencil. The second method is suitable for printing substrates of a certain thickness (e.g., substrates used in the consumer electronics industry). It uses a substrate lifting device and a substrate support device of the stencil printing machine in conjunction with a second-direction drive device for the transfer tray to hold the transfer tray stationary relative to the stencil. Therefore, the stencil printing machine of this application is applicable to stencils of various thicknesses.

[0084] Furthermore, the holding device of this application for thinner templates has a holding member that is retractable in the X direction (third direction), and the holding clip engages with the holding member only when performing solder paste transfer operations, thus not taking up too much of the compact space under the printhead gantry.

[0085] Although this application has been described with reference to examples of the embodiments outlined above, various alternatives, modifications, variations, improvements, and / or substantially equivalents, whether known or currently or soon to be foreseen, will likely be apparent to those skilled in the art. Furthermore, the technical effects and / or technical problems described herein are exemplary and not limiting; therefore, the disclosures herein may be used to solve other technical problems and have other technical effects and / or can solve other technical problems. Thus, the examples of embodiments of this application as set forth above are intended to be illustrative and not limiting. Various changes can be made without departing from the spirit or scope of this application. Therefore, this application is intended to include all known or previously developed alternatives, modifications, variations, improvements, and / or substantially equivalents.

Claims

1. A template printing machine for printing assembly materials on electronic substrates, characterized in that... Comprising: a frame; a print head gantry movably coupled to the frame along a first direction; a transfer device supported by the print head gantry, the transfer device comprising a transfer tray, a first direction cylinder, and a second direction drive, the first direction cylinder comprising a cylinder barrel and a piston rod, the piston rod of the first direction cylinder having a free moving state relative to the cylinder barrel thereof, the piston rod of the first direction cylinder being coupled to the transfer tray, the cylinder barrel of the first direction cylinder being coupled to the second direction drive.

2. The stencil printer of claim 1, further comprising: the first direction cylinder further comprising a piston disposed in the cylinder barrel thereof; wherein the cylinder barrel of the first direction cylinder is provided with a first port and a second port respectively located at opposite sides of the piston, the first port and the second port being controllably communicated with a compressed gas source.

3. The stencil printer of claim 1, further comprising: the second direction drive comprising a second direction cylinder and a second direction additional cylinder, the second direction cylinder being configured to drive the second direction additional cylinder to drive the first direction cylinder and the transfer tray to move along the second direction.

4. The stencil printer of claim 3, further comprising: the second direction cylinder comprising a fixed portion and a movable portion, the fixed portion of the second direction cylinder being connected to the print head gantry, the movable portion of the second direction cylinder being connected to the cylinder barrel of the first direction cylinder; and the second direction additional cylinder comprising a fixed portion and a movable portion, the fixed portion of the second direction additional cylinder being connected to the piston rod of the first direction cylinder, the transfer tray being connected to the movable portion of the second direction additional cylinder.

5. The stencil printer of claim 4, further comprising: a stroke of the second direction additional cylinder being less than a stroke of the second direction cylinder.

6. The stencil printer of claim 1, wherein further comprising: a holding device comprising: a holding member supported by the frame and extendable and retractable along a third direction; and a holding clamp coupled to the transfer tray, the holding clamp being closable and openable to releasably clamp the holding member.

7. The stencil printer of claim 6, further comprising: the holding clamp comprising a pneumatic jaw.

8. The stencil printer of claim 6, further comprising: the holding member comprising a holding piece extending along the first direction with a length. the holding device further comprising:

9. The stencil printer of claim 6, wherein a third direction cylinder drivingly connected to the holding member. the holding device comprising:

10. The stencil printer of claim 6, wherein two of the holding members respectively located at opposite sides of the transfer tray along the third direction, and two of the holding clamps respectively cooperating with the two of the holding members. ​

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