Anti-oxidation coating wear resistance detection device

Abstract

The invention relates to the technical field of wear resistance detection, and discloses an anti-oxidation coating wear resistance detection device which comprises a performance detection device body, and a damping adjusting mechanism is arranged at the top of the performance detection device body; according to the anti-oxidation coating polishing device, through the arranged damping adjusting mechanism, when a user needs to polish an anti-oxidation coating workpiece and needs to adjust damping of an extrusion spring, the user can rotate a handle, the handle drives a lead screw to rotate, and the user can observe the positions of an index plate and a scale ring to assist in adjusting the number of turns of rotating the lead screw; the positions of the index plate and the scale ring provide visual assistance, so that a user can accurately control the adjusting turns of the lead screw, accurate adjustment of the damping of the extrusion spring is achieved, it is helpful to ensure that the surface of an anti-oxidation coating workpiece is evenly polished, and coating damage or irregular surfaces caused by uneven pressure are avoided.

Description

Technical Field

[0001] The invention relates to the technical field of wear resistance detection, and in particular to a wear resistance detection device for an anti-oxidation coating. Background Art

[0002] With the continuous progress of industrial manufacturing and materials science, antioxidant coatings, as an advanced surface protection technology, have been widely used in aerospace, automobile manufacturing, energy equipment, and chemical industries. This type of coating can significantly improve the durability of materials in extreme environments by forming a dense and stable protective film on the surface of the substrate. It can not only effectively prevent the penetration of oxygen and water vapor, thereby preventing material oxidation, but also enhance the corrosion resistance, wear resistance, and high temperature resistance of the material. However, although the antioxidant coating has excellent performance, its wear resistance is one of the key factors that determine the actual service life of the coating. In a complex working environment, the antioxidant coating not only needs to withstand high-temperature oxidation and corrosion, It also needs to withstand continuous mechanical friction and impact. If the wear resistance of the coating is insufficient, the coating surface may be partially peeled off or scratched due to mechanical damage, resulting in failure of the protective film. The substrate is directly exposed to the oxidizing and corrosive environment, which ultimately accelerates the aging or damage of the material. Therefore, the detection of the wear resistance of the antioxidant coating has become an important part of the research and development and application of the coating. Through scientific evaluation of the wear resistance of the coating, the wear behavior of the coating under actual use conditions can be accurately understood, thereby guiding the optimization of the coating formulation and process improvement, which can not only ensure the stability and durability of the antioxidant coating in a specific use environment, but also provide a strong guarantee for improving the reliability and economy of industrial equipment.

[0003] According to Chinese patent CN104880376B, a device for detecting the wear resistance of the surface coating of a profile is disclosed, which is basically described as comprising a support frame, a sand hopper arranged on the upper part of the support frame, the discharge port of the sand hopper is connected to the upper end of the conduit, and a workpiece is arranged below the lower end of the conduit. With the above structure, the present invention has the following advantages: 1. By wearing through the quality of the surface coating of the profile, the wear resistance of the surface coating of the profile can be accurately measured, and the sand guide needle plays a role of guiding the falling sand material, so that the falling sand is concentrated, and the sand material concentration is strong; 2. The rotating shaft structure is convenient for adjusting the inclination angle of the profile plate, and also convenient for the installation of the profile plate; 3. The role of the positioning pin is to ensure that the height of the sand material freely falling to the contact with the profile plate is the same each time the sample is tested, reducing the error caused by different heights; 4. The conduit prevents the wind from affecting the free-falling sand material; the lifting mechanism raises the sand material weighing mechanism to the sand hopper, and the sand material in the sand material weighing mechanism flows into the sand hopper to achieve recycling.

[0004] But in practice, there are still some problems: Traditional devices usually lack damping adjustment function, or only rely on fixed pressure for grinding, and cannot be flexibly adjusted according to the hardness or thickness of the anti-oxidation coated workpiece. Since the pressure is not adjustable, it is easy to have problems of excessive or insufficient pressure. Excessive pressure will cause damage or peeling of the coating, seriously affecting the quality of the workpiece. Insufficient pressure cannot effectively remove surface defects, resulting in uneven grinding or low processing efficiency.

[0005] Traditional equipment mostly relies on manual adjustment, the adjustment steps are complicated and time-consuming, the adjustment accuracy depends on the operator's experience, and it is not easy to adapt to large-scale production.

[0006] When replacing the grinding disc of a traditional grinding device, it is usually necessary to use external tools, which involves the disassembly and assembly of multiple parts, and the operation is cumbersome. Summary of the invention

[0007] In view of the deficiencies in the prior art, the present invention provides an anti-oxidation coating wear resistance detection device, which solves the problems that the traditional device lacks damping adjustment, cannot flexibly adjust the pressure, and the traditional grinding disc replacement requires external tools and cumbersome steps.

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions: an antioxidant coating wear resistance detection device, including a performance detection device body, a damping adjustment mechanism is provided on the top of the performance detection device body, and the damping adjustment mechanism includes a mounting plate, a transmission sleeve, a motor, a connecting plate, a limit rod, an extrusion spring, a screw rod, a transmission plate, an adjustment plate, a scale ring, an indicator plate and a handle, the bottom end of the transmission sleeve is fixedly connected to the connecting plate, the middle part of the screw rod is threadedly connected to the adjustment plate, the bottom end of the connecting plate is fixedly connected to the limit rod, the bottom end of the adjustment plate is fixedly connected to the extrusion spring, the bottom end of the extrusion spring is fixedly connected to the transmission plate, the outer wall of the screw rod is fixedly connected to the handle, and the bottom end of the connecting plate is fixedly connected to the scale ring; A mounting mechanism is provided at the bottom of the transmission plate, and the mounting mechanism includes a slide rail, a locking plate, an unlocking plate, a limit groove, a limit piece, an empty groove, a transmission handle, a locking frame and a locking groove. A locking plate is slidably connected to the inner side of the slide rail, a limit groove is provided at the bottom end of the unlocking plate, a limit piece is slidably connected to the inner wall of the limit groove, a grinding disc is fixedly connected to the bottom end of the locking frame, and a locking groove is provided in the middle of the locking frame.

[0009] Preferably, a turntable is rotatably connected to the front of the performance testing device body, an electric lift is internally connected to the performance testing device body, an anti-oxidation coated workpiece is placed on the top of the turntable, and the output end of the electric lift is fixedly connected to the top of the mounting plate.

[0010] Preferably, a motor is fixedly connected to the bottom end of the mounting plate, the top end of the transmission sleeve is rotatably connected to the bottom end of the mounting plate, and the output end of the motor is fixedly connected to the bottom end of the inner wall of the transmission sleeve.

[0011] Preferably, the top end of the screw rod is rotatably connected to the bottom end of the connecting plate, and the adjusting plate is vertically slidably connected to the limiting rod.

[0012] Preferably, the handle is slidably connected to the bottom end of the connecting plate, and an indicator plate is fixedly connected to the outer side of the handle.

[0013] Preferably, the top end of the slide rail is fixedly connected to the bottom end of the transmission plate, and the top end of the unlocking plate is rotatably connected to the bottom end of the slide rail.

[0014] Preferably, the top end of the limiting member is fixedly connected to the locking plate, and one end of the locking plate passes through the locking groove.

[0015] Preferably, an empty slot is provided at the bottom end of the unlocking plate, and a transmission handle is fixedly connected to the bottom end of the unlocking plate, and the transmission handle matches the size of the empty slot. Beneficial Effects

[0016] The present invention provides a device for detecting wear resistance of an anti-oxidation coating. Compared with the prior art, the device has the following beneficial effects: In the present invention, through the provided damping adjustment mechanism, when the user needs to grind the anti-oxidation coated workpiece, the user needs to adjust the damping of the extrusion spring. When adjusting, the user can turn the handle, and the handle drives the screw to rotate. The user can observe the position of the indicator plate and the scale ring to assist in adjusting the number of turns of the screw. The position of the indicator plate and the scale ring provides intuitive assistance, so that the user can accurately control the number of adjustment turns of the screw, thereby achieving precise adjustment of the damping of the extrusion spring, which helps to ensure uniform grinding of the surface of the anti-oxidation coated workpiece, avoid coating damage or irregular surface caused by uneven pressure, and when the screw rotates, the screw drives the adjustment The section plate moves, and the adjustment plate drives the extrusion spring to descend, providing flexible control of the grinding pressure. The grinding pressure can be adjusted according to the hardness or thickness of the workpiece with different anti-oxidation coatings, so as to avoid over-grinding or under-grinding and improve the grinding effect. The limit rod can provide limit and support for the adjustment plate to ensure that the adjustment process is smooth and reliable and the grinding effect will not be affected by shaking. The user can then start the electric lift to descend to grind the workpiece with the anti-oxidation coating. With the use of the electric lift, the adjustment and grinding process is smoother. The electric lift can quickly complete the adjustment of the grinding height, reduce the time of manual intervention, and further improve production efficiency.

[0017] 2. In the present invention, through the installation mechanism provided, when the user needs to replace the grinding disc, the user pulls out the transmission handle from the empty slot and then rotates the transmission handle. During the rotation, the transmission handle drives the unlocking plate to rotate. When the unlocking plate rotates, the limit slot provided at the bottom end thereof can drive the limit member to move, and the limit member moves along the limit slot to drive the locking plate to be removed from the locking frame. Then, the old grinding disc is taken out and the newly replaced grinding disc is attached to the bottom end of the unlocking plate. Then, the user can rotate the transmission handle in the opposite direction. When the unlocking plate rotates, the limit slot provided at the bottom end thereof can drive the limit member to move, and the limit member moves along the limit slot to drive the locking plate to be inserted into the locking slot provided in the middle part of the locking frame, so as to quickly install the grinding disc. On the one hand, it can avoid disassembly and installation with the help of external tools, on the other hand, it can save installation and disassembly time, improve grinding efficiency, and is suitable for grinding discs of various specifications and models, can flexibly respond to different grinding needs, and improve the versatility and application range of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of the three-dimensional structure of an anti-oxidation coating wear resistance detection device proposed by the present invention; Figure 2 This is a schematic diagram of the internal structure of an anti-oxidation coating wear resistance detection device proposed by the present invention; Figure 3 An electric lifter for an anti-oxidation coating wear resistance detection device proposed by the present invention; Figure 4 This is a schematic structural diagram of a transmission sleeve portion of an anti-oxidation coating wear resistance detection device proposed by the present invention; Figure 5 The invention provides an anti-oxidation coating wear resistance detection device Figure 4 Enlarged view of point A in the middle; Figure 6 A structural cross-sectional view of a connecting plate portion of an anti-oxidation coating wear resistance detection device proposed by the present invention; Figure 7 The invention provides an anti-oxidation coating wear resistance detection device Figure 6 Enlarged view of point B in the middle.

[0019] Legend: 1. Performance testing device body; 2. Turntable; 3. Anti-oxidation coating workpiece; 4. Electric lift; 5. Damping adjustment mechanism; 501. Mounting plate; 502. Transmission sleeve; 503. Motor; 504. Connecting plate; 505. Limit rod; 506. Extrusion spring; 507. Screw rod; 508. Transmission plate; 509. Adjustment plate; 510. Scale ring; 511. Index plate; 512. Handle; 6. Grinding disc; 7. Mounting mechanism; 701. Slide rail; 702. Locking plate; 703. Unlocking plate; 704. Limiting slot; 705. Limiting piece; 706. Empty slot; 707. Transmission handle; 708. Locking frame; 709. Locking slot. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] See also Figure 1-Figure 7 The present invention provides two technical solutions, which specifically include the following embodiments: Embodiment 1

[0022] A device for detecting wear resistance of an antioxidant coating comprises a performance detection device body 1. A damping adjustment mechanism 5 is provided on the top of the performance detection device body 1. The damping adjustment mechanism 5 comprises a mounting plate 501, a transmission sleeve 502, a motor 503, a connecting plate 504, a limiting rod 505, an extrusion spring 506, a screw 507, a transmission plate 508, an adjustment plate 509, a scale ring 510, an indicator plate 511 and a handle 512. The bottom end of the transmission sleeve 502 is fixedly connected to the connecting plate 504, the middle part of the screw 507 is threadedly connected to the adjustment plate 509, the bottom end of the connecting plate 504 is fixedly connected to the limiting rod 505, the bottom end of the adjustment plate 509 is fixedly connected to the extrusion spring 506, the bottom end of the extrusion spring 506 is fixedly connected to the transmission plate 508, the outer wall of the screw 507 is fixedly connected to the handle 512, and the bottom end of the connecting plate 504 is fixedly connected to the scale ring 510.

[0023] Preferably, the front of the performance testing device body 1 is rotatably connected to a turntable 2, the interior of the performance testing device body 1 is connected to an electric lift 4, an anti-oxidation coated workpiece 3 is placed on the top of the turntable 2, and the output end of the electric lift 4 is fixedly connected to the top of the mounting plate 501.

[0024] In the above-mentioned components, the anti-oxidation coating workpiece 3 has the anti-oxidation coating applied to the surface of the workpiece so as to test the performance of the anti-oxidation coating. During the test, the user places the anti-oxidation coating workpiece 3 on the turntable 2 for fixing, and then the user can start the electric lift 4 so that the grinding disc 6 fits the surface of the anti-oxidation coating workpiece 3 to test it.

[0025] Preferably, the bottom end of the mounting plate 501 is fixedly connected to a motor 503 , the top end of the transmission sleeve 502 is rotatably connected to the bottom end of the mounting plate 501 , and the output end of the motor 503 is fixedly connected to the bottom end of the inner wall of the transmission sleeve 502 .

[0026] Among the above components, the motor 503 is the driving force, which enables it to quickly transmit power to related components to achieve higher work efficiency, and can drive the transmission sleeve 502 to rotate, and the transmission sleeve 502 can drive the connecting plate 504 to rotate.

[0027] Preferably, the top end of the screw rod 507 is rotatably connected to the bottom end of the connecting plate 504 , and the adjusting plate 509 is vertically slidably connected to the limiting rod 505 .

[0028] Among the above components, the adjustment plate 509 is made of stainless steel, which has good hardness and wear resistance, and can not only withstand a large extrusion force, but also maintain a long service life in high-frequency use. At the same time, the height of the adjustment plate 509 can be flexibly adjusted by rotating the screw 507, which is easy to operate and can meet the needs of different working scenes. It not only improves the working accuracy and reliability of the equipment, but also makes it more adaptable and suitable for grinding workpieces of various specifications and hardness.

[0029] Preferably, the handle 512 is slidably connected to the bottom end of the connecting plate 504 , and the outer side of the handle 512 is fixedly connected to the indicator plate 511 .

[0030] In the above-mentioned components, the handle 512 drives the indicator plate 511 to rotate synchronously, and the indicator mark on the indicator plate 511 cooperates with the scale ring 510, so that the user can intuitively observe and judge the rotation angle or number of circles. As the angle of the indicator plate changes, the user can make precise adjustments according to the marks on the scale ring 510, thereby more accurately controlling the rotation of the screw rod 507. This not only improves the accuracy of the operation and ensures the reliability of the equipment in high-demand scenarios, but also simplifies the use process, making the operation more convenient and easy to master. At the same time, the structural design is also highly adaptable and can meet the adjustment needs of different workpieces.

[0031] During operation: When the user needs to grind the anti-oxidation coated workpiece 3, the user needs to adjust the damping of the extrusion spring 506. During adjustment, the user can turn the handle 512, and the handle 512 drives the screw rod 507 to rotate. The user can observe the positions of the indicator plate 511 and the scale ring 510 to assist in adjusting the number of turns of the screw rod 507. The positions of the indicator plate 511 and the scale ring 510 provide intuitive assistance, allowing the user to accurately control the number of adjustment turns of the screw rod 507, thereby achieving precise adjustment of the damping of the extrusion spring 506, which helps to ensure uniform grinding of the surface of the anti-oxidation coated workpiece 3 and avoid coating damage or irregular surface caused by uneven pressure. When the screw rod 507 rotates, the screw rod 507 The adjustment plate 509 is then driven to move, and the adjustment plate 509 thereby drives the extrusion spring 506 to descend, providing flexible control of the grinding pressure, and being able to adjust the grinding pressure according to the hardness or thickness of the workpiece 3 with different anti-oxidation coatings, thereby avoiding over-grinding or under-grinding and improving the grinding effect. The limit rod 505 can provide limiting and support for the adjustment plate 509, ensuring that the adjustment process is smooth and reliable and the grinding effect will not be affected by shaking. Subsequently, the user can start the electric lift 4 to descend, thereby grinding the workpiece 3 with the anti-oxidation coating. With the use of the electric lift 4, the adjustment and grinding process is smoother, and the electric lift 4 can quickly complete the adjustment of the grinding height, thereby reducing the time of manual intervention and further improving production efficiency. Embodiment 2

[0032] On the basis of embodiment 1, a mounting mechanism 7 is provided at the bottom of the transmission plate 508, and the mounting mechanism 7 includes a slide rail 701, a locking plate 702, an unlocking plate 703, a limiting groove 704, a limiting piece 705, an empty groove 706, a transmission handle 707, a locking frame 708 and a locking groove 709. The inner side of the slide rail 701 is slidably connected with the locking plate 702, the bottom end of the unlocking plate 703 is provided with a limiting groove 704, the inner wall of the limiting groove 704 is slidably connected with the limiting piece 705, the bottom end of the locking frame 708 is fixedly connected with a grinding disc 6, and a locking groove 709 is provided in the middle of the locking frame 708.

[0033] Preferably, the top end of the slide rail 701 is fixedly connected to the bottom end of the transmission plate 508 , and the top end of the unlocking plate 703 is rotatably connected to the bottom end of the slide rail 701 .

[0034] Among the above components, the function of the slide rail 701 is mainly to provide reliable limiting and guiding functions for the locking plate 702, ensuring that the locking plate 702 always maintains an accurate path during movement to avoid offset or jamming. When the unlocking plate 703 rotates, the limiting groove 704 opened at its bottom can drive the limiting member 705 to slide smoothly along the slide rail 701, thereby driving the locking plate 702 to achieve the corresponding unlocking or locking operation. The cooperation between the slide rail 701 and the limiting groove 704 not only improves the stability and reliability of the device during operation, but also ensures the efficiency and accuracy of the unlocking and locking actions.

[0035] Preferably, the top end of the limiting member 705 is fixedly connected to the locking plate 702 , and one end of the locking plate 702 passes through the locking groove 709 .

[0036] In the above-mentioned components, the locking plate 702 is inserted into the locking groove 709 to firmly fix the transmission component or other device on the locking frame 708, thereby achieving a stable installation effect. The fixed connection between the limit member 705 and the locking plate 702 enables the limit member 705 to reliably drive the locking plate 702 to insert into or move out of the locking groove 709 when moving along the slide rail 701, thereby completing the unlocking or locking function.

[0037] Preferably, an empty slot 706 is formed at the bottom end of the unlocking plate 703 , and a transmission handle 707 is fixedly connected to the bottom end of the unlocking plate 703 , and the transmission handle 707 matches the size of the empty slot 706 .

[0038] Among the above components, the empty slot 706 is mainly used to store and limit the transmission handle 707. When the transmission handle 707 is not in use, it can be conveniently stored in the empty slot 706 to reduce the occupied space and keep the device tidy. At the same time, when the user needs to operate the unlocking plate 703, the transmission handle 707 can be easily taken out of the empty slot 706, and the matching design ensures that the operation process is smooth and accurate.

[0039] When the user needs to replace the grinding disc 6 during operation, the user pulls out the transmission handle 707 from the empty slot 706, and then rotates the transmission handle 707. During the rotation, the transmission handle 707 drives the unlocking plate 703 to rotate. When the unlocking plate 703 rotates, the limiting slot 704 at the bottom end thereof can drive the limiting member 705 to move. The limiting member 705 moves along the limiting slot 704 to drive the locking plate 702 to move out of the locking frame 708, and then the old grinding disc 6 is taken out, and the newly replaced grinding disc 6 is attached to the bottom end of the unlocking plate 703. Then the user can reversely rotate the transmission handle 7 07. When the unlocking plate 703 rotates, the limiting groove 704 at its bottom end can drive the limiting member 705 to move. The limiting member 705 moves along the limiting groove 704 to drive the locking plate 702 to be inserted into the locking groove 709 opened in the middle of the locking frame 708, so as to quickly install the grinding disc 6. On the one hand, it can avoid the need for disassembly and installation with the help of external tools, and on the other hand, it can save installation and disassembly time, improve grinding efficiency, and is suitable for grinding discs 6 of various specifications and models, can flexibly respond to different grinding needs, and improve the versatility and applicability of the equipment.

[0040] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the application should be included in the protection scope of the present application.

Claims

1. A wear resistance detection device for an anti-oxidation coating, comprising a performance detection device body (1), characterized in that: The top of the performance detection device body (1) is provided with a damping adjustment mechanism (5), the damping adjustment mechanism (5) comprising a mounting plate (501), a transmission sleeve (502), a motor (503), a connecting plate (504), a limit rod (505), an extrusion spring (506), a screw rod (507), a transmission plate (508), an adjustment plate (509), a scale ring (510), an indicator plate (511) and a handle (512), the bottom end of the transmission sleeve (502) being fixedly connected to a connecting rod (511). A connecting plate (504), the middle part of the screw rod (507) is threadedly connected to an adjusting plate (509), the bottom end of the connecting plate (504) is fixedly connected to a limiting rod (505), the bottom end of the adjusting plate (509) is fixedly connected to an extrusion spring (506), the bottom end of the extrusion spring (506) is fixedly connected to a transmission plate (508), the outer wall of the screw rod (507) is fixedly connected to a handle (512), and the bottom end of the connecting plate (504) is fixedly connected to a scale ring (510); A mounting mechanism (7) is provided at the bottom of the transmission plate (508), and the mounting mechanism (7) comprises a slide rail (701), a locking plate (702), an unlocking plate (703), a limiting groove (704), a limiting member (705), an empty groove (706), a transmission handle (707), a locking frame (708) and a locking groove (709); the inner side of the slide rail (701) is slidably connected to the locking plate (702); the bottom end of the unlocking plate (703) is provided with a limiting groove (704); the inner wall of the limiting groove (704) is slidably connected to the limiting member (705); the bottom end of the locking frame (708) is fixedly connected to a grinding disc (6); and the middle part of the locking frame (708) is provided with a locking groove (709).

2. The anti-oxidation coating wear resistance detection device according to claim 1, characterized in that: The front side of the performance testing device body (1) is rotatably connected to a turntable (2), the interior of the performance testing device body (1) is connected to an electric lift (4), an anti-oxidation coated workpiece (3) is placed on the top of the turntable (2), and the output end of the electric lift (4) is fixedly connected to the top of the mounting plate (501).

3. The wear resistance detection device for anti-oxidation coating according to claim 1 is characterized in that: The bottom end of the mounting plate (501) is fixedly connected to a motor (503), the top end of the transmission sleeve (502) is rotatably connected to the bottom end of the mounting plate (501), and the output end of the motor (503) is fixedly connected to the bottom end of the inner wall of the transmission sleeve (502).

4. The wear resistance detection device for anti-oxidation coating according to claim 1, characterized in that: The top end of the screw rod (507) is rotatably connected to the bottom end of the connecting plate (504), and the adjusting plate (509) is vertically slidably connected to the limiting rod (505).

5. The wear resistance detection device for anti-oxidation coating according to claim 1, characterized in that: The handle (512) is slidably connected to the bottom end of the connecting plate (504), and an indicator plate (511) is fixedly connected to the outer side of the handle (512).

6. The wear resistance detection device for anti-oxidation coating according to claim 1, characterized in that: The top end of the slide rail (701) is fixedly connected to the bottom end of the transmission plate (508), and the top end of the unlocking plate (703) is rotatably connected to the bottom end of the slide rail (701).

7. The wear resistance detection device for anti-oxidation coating according to claim 1 is characterized in that: The top end of the limiting member (705) is fixedly connected to the locking plate (702), and one end of the locking plate (702) passes through the locking groove (709).

8. The wear resistance detection device for anti-oxidation coating according to claim 1, characterized in that: An empty slot (706) is provided at the bottom end of the unlocking plate (703), and a transmission handle (707) is fixedly connected to the bottom end of the unlocking plate (703), wherein the transmission handle (707) matches the size of the empty slot (706).

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