A robotic palletizing system for sheet material

Abstract

This application discloses a robotic palletizing system for sheet metal, including a palletizing robot and a carrying mechanism. The palletizing robot is equipped with a gripping mechanism at its end for gripping sheet metal and stacking it onto the carrying mechanism. The carrying mechanism includes a support base and a retainer. The retainer is disposed on the four sides of the support base and forms a carrying area. The retainer includes a plurality of serially connected partition blocks. The partition blocks can be placed under the bottom of the sheet metal under the drive of a drive mechanism and can be removed from the bottom of the sheet metal when it is removed. After the robot drives the gripping mechanism to pick up the sheet metal and places it in the carrying area, the drive mechanism can automatically add partition blocks to the bottom of the sheet metal after each sheet metal is placed. Moreover, the partition blocks can be removed when the sheet metal is removed to avoid affecting the handling of the next sheet metal. This eliminates the need for manual operation and additional robot operation, which helps to improve palletizing efficiency and reduce costs.

Description

Technical Field

[0001] This application belongs to the field of industrial automation, and specifically relates to a robotic palletizing system for sheet metal. Background Technology

[0002] With the development of industrial automation, more and more repetitive tasks are being handled by robots instead of manual labor, such as loading and unloading products and palletizing them.

[0003] During the stacking of sheet materials, especially fragile materials such as ceramic tiles and glass, direct stacking can easily cause damage due to bumps and knocks. If cushioning materials are manually placed between the sheets, the added step reduces stacking efficiency. Furthermore, manual handling increases the risk of scratches from the sharp edges of the sheets. Adding a robot to stack and place cushioning materials simultaneously significantly increases the cost of the robotic stacking system, hindering cost reduction and efficiency improvement.

[0004] Therefore, a robotic palletizing system for fragile boards is needed to solve the above problems. Summary of the Invention

[0005] To address the shortcomings of the prior art, this application provides a robotic palletizing system for sheet metal, which can automatically add insulating buffers between sheets to prevent them from bumping and rubbing against each other, thus greatly improving palletizing efficiency.

[0006] The technical effect to be achieved in this application is accomplished through the following solution:

[0007] According to a first aspect of this application, a robotic palletizing system for sheet metal is provided, including a palletizing robot and a carrying mechanism. The palletizing robot is provided with a gripping mechanism at its end for gripping sheet metal and stacking it onto the carrying mechanism. The carrying mechanism includes a support base and a retainer. The retainer is disposed on the four sides of the support base and forms a carrying area. The retainer includes a plurality of serially connected partition blocks. The partition blocks can be placed on the bottom of the sheet metal under the drive of a drive mechanism and can be removed from the bottom of the sheet metal when it is removed.

[0008] With this solution, after the robot drives the gripping mechanism to pick up the board and place it in the carrying area, the drive mechanism can automatically add a separator block to the bottom of the board after each board is placed. Moreover, the separator block can be removed when the board is removed to avoid affecting the handling of the next board. No manual or extra robot operation is required, which helps to improve palletizing efficiency and reduce costs.

[0009] Preferably, the partition block includes a connecting block and a partition plate. The upper and lower adjacent connecting blocks are connected by a connecting rod, and the connecting rod is rotatably connected to the connecting block. The partition plate is fixed to the side of the connecting block facing the bearing area.

[0010] With this solution, the distance between the partitions is consistent with the thickness of the board, the connecting blocks are connected and stacked together to provide support, gaps can be reserved between the partitions for the board to be placed, and the partitions can extend into the middle of the load-bearing area to improve the separation and support functions.

[0011] Preferably, the partition block is arranged vertically in the bearing area and bends outward at the stacking height of the plates to form a driving part, so that the partition plate at the bottom of the driving part can be pressed down to complete the stacking when the plates are stacked.

[0012] This solution automatically separates the boards each time they are placed, without the need for an external drive device. It relies solely on the downward pressure of the boards to achieve automatic separation, resulting in a clever structure and low cost.

[0013] Preferably, the upper and lower sides of the partition plate are provided with buffer pads.

[0014] With this solution, the cushioning pad, such as a sponge, can further enhance the cushioning effect.

[0015] Preferably, the support seat is provided with a cavity around it, the drive mechanism is disposed in the cavity and is connected to the partition block at the far end by a pull rope and a fixed pulley, and the fixed pulley is fixed directly below the opening of the cavity.

[0016] With this solution, the cavity allows the partition block to extend downwards beyond the load-bearing area, reserving enough space for the drive unit to reach the bottom layer, so that the second plate can squeeze the drive unit to complete the partition.

[0017] Preferably, the drive mechanism includes a take-up drum and a driver, the driver driving the take-up drum to rotate, and the pull rope being wound onto the take-up drum.

[0018] With this solution, the driver can control the length of the pull rope of the winding drum. The pull force is less than the weight of the board, so that when the board is placed on the bottom partition block of the drive unit, a section of the pull rope can be released under the pull of the partition block to complete the upward movement of the drive unit; when the board is removed, the pull rope can be pulled to move the partition block away from the next board.

[0019] Preferably, the gripping mechanism includes a mounting plate connected to the robot, the bottom surface of the mounting plate is provided with a plurality of suction cups, and a pad release mechanism is also installed on the mounting plate. The pad release mechanism is used to stick the pad to the currently adsorbed board, and the height of the pad is consistent with the distance between the stacked boards.

[0020] This solution involves attaching pads to the center of the board during placement to support it and prevent damage, friction, and breakage caused by the board collapsing when it is too large. It eliminates the need for manual or additional robotic operation, reducing costs and improving efficiency.

[0021] Preferably, the pad release mechanism includes a storage cylinder and a release cover. The storage cylinder passes through the mounting plate and is fixed to the release cover. The release cover is provided with a baffle and a pusher. The pusher drives the baffle to block or move the discharge port of the release cover.

[0022] In this solution, the storage cylinder is used to store pads. When the suction cup is attached to the board, the pusher is activated to remove the baffle, so that the pad at the bottom is attached to the board. After the boards are stacked, the baffle is used to block the discharge port, waiting for the next release.

[0023] Preferably, the bottom of the baffle is hinged to the receiving cavity at the bottom of the release cover, the pusher includes a push rod and a torsion spring, the baffle is connected to the release cover through the torsion spring, the push rod passes through the bottom of the receiving cavity and protrudes from the release cover, and the push rod is slidably connected to the release cover; the bottom of the outer end of the baffle is a guide surface.

[0024] With this solution, after the gripping mechanism presses onto the board, the push rod moves upward under the pressure of the board, driving the baffle to flip upward, thereby pushing open the bottom pad until it is released. The bonding is completed under its own weight and the pressure of the top pad. When the gripping mechanism is lifted, the baffle covers the discharge port again under the action of the torsion spring. The structure is simple and ingenious, and the cost is low.

[0025] Preferably, the storage cylinder is provided with a spring and a push plate, and the spring always applies a pushing force to the push plate toward the release cover.

[0026] With this solution, the spring can push the push plate to apply force to the pad, ensuring that the pad can be effectively released and adhered to the board.

[0027] According to one embodiment of this application, the robotic palletizing system for sheet metal can separate sheet metals through a simple mechanical structure, avoiding collisions and friction between the sheet metals. This not only greatly improves efficiency but also helps to reduce labor and equipment costs. Attached Figure Description

[0028] To more clearly illustrate the embodiments of this application or the existing technical solutions, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of a robotic palletizing system for sheet metal according to one embodiment of this application;

[0030] Figure 2 for Figure 1 A top view of the load-bearing mechanism;

[0031] Figure 3 for Figure 1 Schematic diagram of the central fixation device;

[0032] Figure 4 for Figure 3 Schematic diagram of the middle partition block;

[0033] Figure 5 for Figure 3 Schematic diagram of the middle connecting rod;

[0034] Figure 6 for Figure 1 Schematic diagram of the cross-sectional structure of the bearing seat;

[0035] Figure 7 for Figure 1 A schematic diagram of the gripping mechanism in the middle;

[0036] Figure 8 for Figure 7 A schematic diagram of the gripping mechanism from below;

[0037] Figure 9 for Figure 7 Schematic diagram of the cross-sectional structure of the middle pad release mechanism;

[0038] Figure 10 for Figure 9 A schematic diagram of the structure of the release cover when it is in place with the release pad;

[0039] Figure 11 for Figure 7 A schematic diagram of the cross-sectional structure of the central storage cylinder. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0041] like Figures 1 to 5 As shown, a robotic palletizing system for sheet metal in one embodiment of this application includes a palletizing robot 10 and a carrying mechanism 20. The palletizing robot 10 is provided with a gripping mechanism 11 at its end for gripping sheet metal 30 and stacking it onto the carrying mechanism 20. The carrying mechanism 20 includes a carrying base and a fixing device 21. The fixing device 21 is disposed on the four sides of the carrying base and forms a carrying area 201. The fixing device 21 includes a plurality of serially connected partition blocks 210. The partition blocks 210 can be placed on the bottom of the sheet metal 30 under the drive of the driving mechanism and can be removed from the bottom of the sheet metal 30 when the sheet metal 30 is taken out.

[0042] In this embodiment, after the robot 10 drives the gripping mechanism 11 to pick up the board 30 and place it in the carrying area 201, the drive mechanism can automatically add a separator block 210 to the bottom of the board 30 for each board 30 placed. Moreover, when the board 30 is removed, the separator block 210 can be removed to avoid affecting the removal of the next board 30. No manual operation or extra robot 10 is required, which helps to improve palletizing efficiency and reduce costs.

[0043] In this embodiment, the partition block 210 includes a connecting block 211 and a partition plate 212. Adjacent connecting blocks 211 are connected by a connecting rod 220, which is rotatably connected to the connecting block 211. The partition plate 212 is fixed to the side of the connecting block 211 facing the bearing area 201. A groove is provided at the rear end of the connecting block 211, allowing the ball head of the connecting rod 220 to insert and complete the connection, thus enabling a certain angle adjustment between the connecting blocks 211.

[0044] To improve strength, adjacent connecting blocks 211 are connected by at least two connecting rods 220, which also allows for vertical angle adjustment without flipping in the horizontal direction.

[0045] The distance between the partition plates 212 is consistent with the thickness of the plate 30. The connecting blocks 211 are connected and stacked together to provide support. There are gaps between the partition plates 212 for the plate 30 to be placed. The partition plates 212 can extend into the middle of the bearing area 201 to improve the separation and support functions.

[0046] like Figure 3As shown, the partition blocks 210 are arranged vertically in the bearing area 201. Since the partition blocks 210 can rotate relative to each other after being connected by the connecting rods 220, the fixtures 21 composed of the partition blocks 210 can be bent. The part that bends outward according to the stacking height of the plates 30 is the driving part 202. The distance between the fixtures 21 is consistent with the size of the plates 30. When the plates 30 are stacked, the partition plate 212 at the bottom of the driving part 202 can be pressed down to complete the stacking.

[0047] The angle of the partition block 210 on the curved part of the retainer 21 is such that the tilt angle of the bottom partition block 210 of the drive unit 202 is just enough to be pressed down by the plate 30 that is about to be stacked, and automatically placed on the bottom of the plate 30; while the tilt angle of the second partition block 210 at the bottom of the drive unit 202 can avoid the plate 30 below, so as to avoid interfering with its placement. After the plate 30 is placed and the bottom partition block 210 of the drive unit 202 is pressed, the second to last partition block 210 completes the angle change, so that the drive unit 202 moves up one partition block 210.

[0048] Therefore, each placement of the board 30 can automatically complete the separation without the need for an external drive device. The automatic separation can be completed solely by the downward pressure of the board 30, resulting in a clever structure and low cost.

[0049] In one embodiment of this application, buffer pads 213 are provided on both the upper and lower sides of the partition plate 212. The buffer pads 213 are made of materials such as sponge or rubber, which can further play a buffering role. The rubber buffer pads 213 can also increase the friction between the buffer pads and the plates 30, making the stacked plates 30 more stable and preventing the stack of plates 30 from tipping over due to mutual sliding.

[0050] In this embodiment, the carrier 20 is placed, for example, as an AGV trolley, which can directly transport the material to the corresponding location for unloading; or it can be a pallet, which is transferred by forklift after stacking.

[0051] like Figure 6 As shown, the support base has cavities 22 around its perimeter. The drive mechanism is located within these cavities and is connected to the end-end partition block 210 via a pull rope 232 and a fixed pulley 233. The fixed pulley 233 is fixed directly below the opening of the cavity 22. The cavity 22 allows the partition block 210, which bends out of the support area 201, to extend downwards, providing sufficient space for the drive unit 202 to reach the bottom layer, enabling the second plate 30 to compress the drive unit 202 to complete the partitioning.

[0052] Since the length of the retainer 21 is fixed, in the initial stage of stacking the plates 30, the bending point of the retainer 21 needs to be low enough to allow the plates 30 to squeeze the current angled divider block 210. Therefore, the other end of the retainer 21 needs to extend downwards long enough. The cavity 22 not only solves this problem, but also hides the end of the retainer 21, which plays a protective role and facilitates connection with the bottom drive mechanism, making it more aesthetically pleasing.

[0053] The driving mechanism in this embodiment includes a take-up drum 231 and a driver. The driver drives the take-up drum 231 to rotate, and the pull rope 232 is wound onto the take-up drum 231. The driver can control the length of the pull rope 232 by driving the take-up drum 231. Its tension is less than the weight of the plate 30, so that when the plate 30 is placed on the bottom partition block 210 of the driving part 202, a section of the pull rope 232 can be released under the pull of the partition block 210 to complete the upward movement of the driving part 202; when the plate 30 is removed, the pull rope 232 can be pulled to move the partition block 210 away from the next plate 30.

[0054] The driver, such as a servo motor or stepper motor, only provides preload during the stacking of the plates 30, ensuring that the drive unit 202 can rise with the stacking height without releasing the retainer 21, causing it to rise at once to two or more partition blocks 210. Only during the unloading process of the plates 30 will the pull rope 232 be wound up as the unloading process proceeds, causing the partition blocks 210 to move away from the top of the plates 30 one by one.

[0055] The driver can also be driven by elastic materials such as torsion springs. During the loading process, pulling out the pull rope 232 will store elastic potential energy. When the plate 30 is unloaded, the stored elastic potential energy is used to pull the fixing device 21 downward, so that the driving part 202 gradually moves down.

[0056] like Figures 7 to 11 As shown, the gripping mechanism 11 in this embodiment includes a mounting plate 110 connected to the robot 10. The bottom surface of the mounting plate 110 is provided with a plurality of suction cups 120. A pad release mechanism 130 is also installed on the mounting plate 110. The pad release mechanism 130 is used to stick the pad 133 to the currently adsorbed board 30. The height of the pad 133 is consistent with the distance between the stacked boards 30.

[0057] Because large materials such as glass plates can sag and break when placed, this embodiment incorporates a pad 133 attached to the center of the plate 30 during placement to support it and prevent damage, friction, and breakage caused by the plate 30 collapsing when it is too large. This eliminates the need for manual or additional robot 10 operation, reducing costs and improving efficiency.

[0058] The suction cup 120 can be replaced as needed. For example, when the plate 30 is glass, ceramic tile, etc., a vacuum suction cup 120 can be used, which is connected to the negative pressure mechanism by a flexible hose; if it is iron plate, an electromagnetic suction cup 120 can be used.

[0059] The pad release mechanism 130 in this embodiment includes a storage cylinder 131 and a release cover 132. The storage cylinder 131 passes through the mounting plate 110 and is fixed to the release cover 132. The release cover 132 is provided with a baffle 135 and a pusher 134. The pusher 134 drives the baffle 135 to block or move the discharge port of the release cover 132.

[0060] The storage cylinder 131 is used to store the pad 133. When the suction cup 120 is attached to the plate 30, the pusher 134 is activated to remove the baffle 135, so that the pad 133 at the bottom is attached to the plate 30. After the plates 30 are stacked, the baffle 135 is used to block the discharge port, waiting for the next release.

[0061] The bottom of the baffle 135 is hinged to the receiving cavity 1321 at the bottom of the release cover 132. The pusher 134 includes a push rod 1341 and a torsion spring. The baffle 135 is connected to the release cover 132 through the torsion spring. The push rod 1341 passes through the bottom of the receiving cavity 1321 and protrudes from the release cover 132. The push rod 1341 is slidably connected to the release cover 132. The bottom of the outer end of the baffle 135 is a guide surface. The thickness of the pad 133 is greater than the length of the baffle 135. When the pad 133 is pasted to the plate 30, the top pad 133 will fall and will not prevent the baffle 135 from returning to its position.

[0062] After the gripping mechanism 11 presses onto the plate 30, the push rod 1341 moves upward under the pressure of the plate 30, driving the baffle 135 to flip upward, thereby pushing open the bottom pad 133 until it is released. The pasting is completed under its own weight and the pressure of the top pad 133. When the gripping mechanism 11 is lifted, the baffle 135 covers the discharge port again under the action of the torsion spring. The structure is simple and ingenious, and the cost is low.

[0063] The size of the rubber strip at the bottom of the pad 133 is smaller than the size of the pad 133, so that a certain gap is reserved between the pads 133. During the process of the bottom pad 133 being removed, the guide surface at the end of the baffle 135 is pressed against the side wall of the pad 133, and the tip of its end can be inserted into the gap between the pads 133 in time under the action of the torsion spring, preventing the top pad 133 from falling out of the discharge port, and thus blocking it again to the bottom of the top pad 133.

[0064] In this embodiment, the storage cylinder 131 is provided with a spring 1311 and a push plate 1312. The spring 1311 always applies a pushing force to the push plate 1312 toward the release cover 132. The spring 1311 can push the push plate 1312 to apply a pushing force to the pad 133, ensuring that the pad 133 can be effectively released and adhered to the plate 30.

[0065] When this device is in use, the drive mechanism is first used to pull the fixture 21 to the bottom. After the robot 10 grabs the plate 30, it is placed in the bearing area 201, so that the bottom of the plate 30 is padded with the first layer of partition plates 212.

[0066] Robot 10 continues to grasp board 30. When it reaches the top of the carrying area 201 and moves vertically downward, the board 30 can be pressed against the raised partition 212 around its perimeter, causing the partition 210 to rotate to a horizontal position until it is placed at the bottom of the board 30 to complete the placement of the second board 30. At the same time, since the current partition 210 is in a horizontal position, it will drive the top partition 210 to rotate towards the carrying area 201 at a certain angle until it enters the carrying area 201, waiting for the next board 30 to be placed, until the stacking operation is completed.

[0067] Once the palletizing is complete and the board is moved to the appropriate location, if it is necessary to unload the board 30, the board 30 is picked up by the robot 10 or manually and moved out of the carrying area 201. After the board 30 is removed from the partition plate 212, due to the pulling force of the drive mechanism, the top partition block 210 will rotate and tilt in the direction away from the carrying area 201 to avoid interfering with the removal of the bottom board 30, until the last board 30 is removed.

[0068] According to one embodiment of this application, the robotic palletizing system for sheet metal can separate sheet metals through a simple mechanical structure, avoiding collisions and friction between the sheet metals. This not only greatly improves efficiency but also helps to reduce labor and equipment costs.

[0069] It should be noted that the above detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0070] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0071] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0072] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or apparatus.

[0073] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways, such as rotated 90 degrees or in other orientations, and the spatial relative descriptions used herein will be interpreted accordingly.

[0074] In the detailed description above, reference has been made to the accompanying drawings, which form part of this document. In the drawings, similar symbols typically identify similar parts unless the context otherwise indicates otherwise. The illustrated embodiments described in the detailed specification, drawings, and claims are not intended to be limiting. Other embodiments may be used and other changes may be made without departing from the spirit or scope of the subject matter presented herein.

[0075] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A robotic palletizing system for sheet metal, comprising a palletizing robot and a support mechanism, wherein the palletizing robot is equipped with a gripping mechanism at its end for gripping sheet metal and stacking it onto the support mechanism, characterized in that, The bearing mechanism includes a bearing base and a fixing device. The fixing device is disposed on the four sides of the bearing base and forms a bearing area. The fixing device includes a plurality of serially connected partition blocks. The partition blocks can be placed to the bottom of the plate under the drive of the driving mechanism and can be removed from the bottom of the plate when the plate is removed. The gripping mechanism includes a mounting plate connected to the robot. The bottom surface of the mounting plate is provided with several suction cups. A pad release mechanism is also installed on the mounting plate. The pad release mechanism is used to stick the pad to the currently adsorbed board. The height of the pad is consistent with the distance between the stacked boards. The pad release mechanism includes a storage cylinder and a release cover. The storage cylinder passes through the mounting plate and is fixed to the release cover. The release cover is provided with a baffle and a pusher. The pusher drives the baffle to block or move the discharge port of the release cover. The bottom of the baffle is hinged to the receiving cavity at the bottom of the release cover. The pusher includes a push rod and a torsion spring. The baffle is connected to the release cover through the torsion spring. The push rod passes through the bottom of the receiving cavity and protrudes from the release cover. The push rod is slidably connected to the release cover. The bottom of the outer end of the baffle is a guide surface.

2. The robotic palletizing system for sheet metal according to claim 1, characterized in that, The partition block includes a connecting block and a partition plate. The upper and lower adjacent connecting blocks are connected by a connecting rod. The connecting rod is rotatably connected to the connecting block. The partition plate is fixed to the side of the connecting block facing the bearing area.

3. The robotic palletizing system for sheet metal according to claim 2, characterized in that, The partition block is arranged vertically in the bearing area and bends outward to form a driving part according to the stacking height of the plates. When the plates are stacked, the partition plate at the bottom of the driving part can be pressed down to complete the stacking.

4. The robotic palletizing system for sheet metal according to claim 3, characterized in that, The upper and lower sides of the partition plate are provided with cushioning pads.

5. The robotic palletizing system for sheet metal according to claim 3, characterized in that, The support seat is provided with a cavity around it, the drive mechanism is disposed in the cavity and is connected to the partition block at the far end by a pull rope and a fixed pulley, and the fixed pulley is fixed directly below the opening of the cavity.

6. The robotic palletizing system for sheet metal according to claim 5, characterized in that, The drive mechanism includes a take-up drum and a driver, the driver driving the take-up drum to rotate, and the pull rope being wound onto the take-up drum.

7. The robotic palletizing system for sheet metal according to claim 1, characterized in that, The storage cylinder is equipped with a spring and a push plate, and the spring always applies a pushing force to the push plate toward the release cover.

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