High-speed sawing band sawing machine for aluminum materials
By using synchronous toothed belt drive, nitrogen cylinder counterweight, and support device guidance, the problem of saw beam instability was solved, achieving stability and precision in high-speed aluminum band sawing, and improving cutting accuracy and efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-20
- Publication Date
- 2026-03-17
AI Technical Summary
The uneven weight of the saw beam in existing band saws causes uneven stress on the linear guide rail, which is prone to deformation, resulting in instability in the upward and downward movement of the saw beam and inaccurate displacement.
The band saw is driven by a synchronous toothed belt, and a nitrogen cylinder is used to counterweight and support the saw beam. The rotation of the band saw is guided by the support device, and a servo motor drives the lead screw and linear guide to ensure the stability and precise movement of the saw beam.
This design enables stable up-and-down movement of the saw beam, improving cutting accuracy and efficiency, reducing lateral forces on the linear guide rail and lead screw, and ensuring the stability and precision of sawing.
Smart Images

Figure CN223997448U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a high-speed band saw for cutting aluminum materials. Background Technology
[0002] Band saws are the main equipment used for cutting long aluminum materials. In existing band saws, the up and down movement of the saw beam is driven by a lead screw. However, the weights on both ends of the saw beam are different. One side of the saw beam is a drive-rotating band saw wheel equipped with a motor. Therefore, the weight of the saw beam is uneven at one end and lighter at the other. This causes uneven force on the linear guide rails on both sides, which can easily cause deformation of the linear guide rails, and in turn, deformation of the lead screw. This results in unstable up and down movement of the saw beam and inaccurate displacement.
[0003] To address this, we designed a high-speed aluminum band saw that can support the saw beam, making its upward and downward movements more stable. Utility Model Content
[0004] The technical problem to be solved by this utility model is to provide a high-speed aluminum band saw that can support the saw beam and make the upward and downward movement of the saw beam more stable.
[0005] To solve the above problems, the present invention adopts the following technical solution:
[0006] A high-speed aluminum band saw includes a frame, a processing table fixedly mounted on the frame, a clamping and feeding device movably mounted on the frame, the clamping and feeding device cooperating with the processing table, a gantry frame mounted on the top of the frame, and a sawing assembly mounted on the gantry frame, the sawing assembly sliding vertically along the gantry frame.
[0007] Preferably, the processing table includes a tabletop, a column, and an operating table. The column is supported at the bottom of the tabletop, and its lower end is fixedly installed to the bed frame. A cover plate is installed above the tabletop, and multiple perforated grooves are machined on the surface of the cover plate. A roller is rotatably installed inside the tabletop, and a bearing is fitted between the roller and the tabletop. Part of the roller extends to the outside of the perforated grooves. The operating table is installed on the top of the bed frame and located in front of the tabletop. A band saw groove is formed between the operating table and the tabletop for the sawing assembly to descend.
[0008] Preferably, the clamping and feeding device includes a linear guide rail, a slider, a servo motor, a first lead screw, a slide table, and clamping cylinders. The linear guide rail is installed on the top of the bed frame and located on both sides of the table. The slider cooperates with the linear guide rail. The slide table is fixed to the top of the slider with screws. The top of the slide table is machined with a through groove passing through the table. Multiple clamping cylinders are arranged on the left and right sides. The clamping cylinders are installed on the top of the slide table and located on both sides of the through groove. The movable end of the clamping cylinder is fixedly installed with a clamping plate. The height of the clamping plate is higher than the height of the cover plate. The servo motor is fixed on the top of the bed frame and located below the table. The first lead screw is installed at the output end of the servo motor. The slide table has a first lead screw nut that cooperates with the first lead screw. A through gap corresponding to the band saw groove is formed between two adjacent clamping plates on the same side. A bearing supporting the rotation of the first lead screw is installed through the bed frame.
[0009] Preferably, the sawing assembly includes a first linear guide rail, a first slider, a saw beam, a first servo motor, a first band saw wheel, a second band saw wheel, a tensioning device, a drive motor, and a nitrogen cylinder; multiple first sliders are symmetrically arranged left and right, the first sliders are fixed to the saw beam, the first sliders cooperate with the first linear guide rails, the first linear guide rails are fixedly installed on the gantry frame, and multiple first linear guide rails are arranged in parallel, a support body is installed on the top of the gantry frame, the first servo motor is fixed to the bottom of the support body, the output end of the first servo motor passes upward through the support body and is installed with an active synchronous pulley, a pulley shaft is rotatably installed through the support body, a second lead screw is fixed to the lower end of the pulley shaft, and a passive synchronous pulley is fixed to the upper end of the pulley shaft, the active synchronous pulley... A synchronous toothed belt is installed between the wheel and the passive synchronous pulley. A second screw nut that matches the second screw is installed on the plate surface of the saw beam. The drive motor is fixedly installed through the saw beam. The first band saw wheel is installed at the output end of the drive motor. The tensioning device is installed through the saw beam. The second band saw wheel is rotatably installed through the tensioning device. A band saw is installed between the first band saw wheel and the second band saw wheel. The lower end of the nitrogen cylinder is fixedly installed to the bed frame. A rotating seat is installed on the plate surface of the saw beam. A connecting sleeve is rotatably installed through the rotating seat. The movable end of the nitrogen cylinder is inserted into the connecting sleeve and fixed. A support device for twisting the band saw is also installed through the saw beam. Two support devices are provided, corresponding to both sides of the processing table.
[0010] Preferably, the tensioning device includes a fixed base, which is fixed to the saw beam. Two upper and lower guide rails are installed on the fixed base, and a shaft seat is slidably installed between the two guide rails. A rotating shaft is rotatably installed through the shaft seat. The second band saw wheel is fixedly installed through the rotating shaft. A second servo motor is installed through the fixed base, and a screw is installed at the output end of the second servo motor. The shaft seat has a threaded hole that matches the screw.
[0011] Preferably, the support device includes a base structure, with four or more axles symmetrically arranged at the front and rear of the bottom of the base structure. The axles are fixed to the base structure, and side pressure rollers are mounted on the axles. An upper pressure roller is rotatably installed on the side of the base structure. The band saw passes between the front and rear side pressure rollers, and the upper pressure roller is positioned above the band saw.
[0012] The beneficial effects of this utility model are:
[0013] One advantage is that this device uses a synchronous toothed belt for transmission, ensuring a precise transmission ratio, thereby driving the band saw to move precisely up and down.
[0014] Secondly, the nitrogen cylinder provides counterweight and support for the saw beam, reducing the lateral forces on the second lead screw and the first linear guide rail, and improving the stability of the saw beam during upward and downward movement.
[0015] Thirdly, the use of a support device guides the rotation of the band saw, increasing its stability during rotation and thus improving cutting accuracy. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, 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 of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a schematic diagram of the structure of this utility model;
[0018] Figure 2 A schematic diagram showing the coordination between the clamping and feeding device and the processing table;
[0019] Figure 3 A perspective view of the clamping and feeding device and the processing table;
[0020] Figure 4 This is a schematic diagram of the band saw groove;
[0021] Figure 5 This is a schematic diagram of the sawing assembly;
[0022] Figure 6 This is a schematic diagram of the drive mechanism for the sawing component;
[0023] Figure 7 This is a schematic diagram showing the fit between the first linear guide and the first slider;
[0024] Figure 8 This is a schematic diagram of the installation of the first servo motor;
[0025] Figure 9 This is a schematic diagram of the installation of the tensioning device;
[0026] Figure 10 A three-dimensional view of the tensioning device;
[0027] Figure 11 A schematic diagram of the installation of the support device;
[0028] Figure 12 This is a schematic diagram of the internal structure of the supporting device. Detailed Implementation
[0029] All features disclosed in this specification, or all steps in all disclosed methods or processes, may be combined in any way, except for mutually exclusive features and / or steps.
[0030] Any feature disclosed in this specification (including any appended claims, abstract, and drawings) may be replaced by other equivalent or similar features for a similar purpose, unless specifically stated otherwise. That is, unless specifically stated otherwise, each feature is merely one example of a series of equivalent or similar features.
[0031] In the description of this utility model, it should be understood that the terms "one end", "the other end", "outer side", "upper", "inner side", "horizontal", "coaxial", "center", "end", "length", "outer end", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0032] Furthermore, in the description of this utility model, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0033] In this utility model, unless otherwise explicitly specified and limited, the terms "set," "socket," "connect," "through," and "plug-in" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0034] See Figure 1 The high-speed aluminum band saw shown includes a frame 1, a processing table 2 fixedly mounted on the frame 1, a clamping and feeding device 3 movably mounted on the frame 1, the clamping and feeding device 3 cooperating with the processing table 2, a gantry frame 4 mounted on the top of the frame 1, and a sawing assembly 5 mounted on the gantry frame 4, the sawing assembly 5 sliding vertically along the gantry frame 4.
[0035] In the above technical solution, the workpiece to be sawed is clamped by the clamping and feeding device 3, and sawing is completed by the downward movement of the sawing component 5.
[0036] When continuous sawing is required, the sawing assembly 5 moves upward and detaches from the workpiece. The clamping and feeding device 3 clamps the workpiece and moves backward, pushing the sawn workpiece block along the processing table 2. Then, the clamping and feeding device 3 moves to the next cutting point of the workpiece. After it reaches the next cutting point, it releases the workpiece and resets the clamping and feeding device 3 to the initial position. Then, the sawing assembly 5 begins the next cutting.
[0037] The above-mentioned technical solution has high sawing efficiency.
[0038] See Figure 2 , Figure 3 and Figure 4 As shown, the processing table 2 includes a table plate 21, a column 22, and an operating table 26. The column 22 is supported at the bottom of the table plate 21, and the lower end of the column 22 is fixedly installed to the bed frame 1. A cover plate 23 is installed above the table plate 21. Multiple hollow grooves 24 are machined on the surface of the cover plate 23. A roller 25 is rotatably installed inside the table plate 21. A bearing is fitted between the roller 25 and the table plate 21. Part of the roller 25 extends to the outside of the hollow grooves 24. The operating table 26 is installed on the top of the bed frame 1 and is located in front of the table plate 21. A band saw groove 261 for the sawing assembly 5 to descend is formed between the operating table 26 and the table plate 21.
[0039] In the above technical solution, the sawn workpiece blocks can slide out along the cover plate 23, making the material discharge smoother.
[0040] See Figure 2 , Figure 3 and Figure 4 As shown, the clamping and feeding device 3 includes a linear guide rail 31, a slider 32, a servo motor 33, a first lead screw 34, a slide table 35, and clamping cylinders 36. The linear guide rail 31 is installed on the top of the bed frame 1 and located on both sides of the table 21. The slider 32 cooperates with the linear guide rail 31. The slide table 35 is fixed to the top of the slider 32 by screws. The top of the slide table 35 is machined with a through groove 3555 that passes through the table 21. Multiple clamping cylinders 36 are arranged on the left and right sides. The clamping cylinders 36 are installed on the top of the slide table 35 and located in the through groove 3555. On both sides of 55, clamping plates 37 are fixedly installed on the movable ends of the clamping cylinder 36, and the height of the clamping plates 37 is higher than the height of the cover plate 23; the servo motor 33 is fixed to the top of the bed frame 1 and located below the table 21; the first lead screw 34 is installed at the output end of the servo motor 33; the slide table 35 has a first lead screw nut 321 that cooperates with the first lead screw 34; a passage gap 371 corresponding to the band saw groove 261 is formed between two adjacent clamping plates 37 on the same side; a bearing 344 supporting the rotation of the first lead screw 34 is installed on the bed frame 1.
[0041] In the above technical solution, the first lead screw 34 is rotated by the servo motor 33, which in turn drives the Huatai 35 to move forward and backward along the linear guide rail 31 to complete the unloading of the workpiece.
[0042] See Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 9As shown, the sawing assembly 5 includes a first linear guide rail 51, a first slider 52, a saw beam 53, a first servo motor 54, a first band saw wheel 55, a second band saw wheel 56, a tensioning device 6, a drive motor 57, and a nitrogen cylinder 58. Multiple first sliders 52 are symmetrically arranged on the left and right sides. The first sliders 52 are fixed to the saw beam 53. The first sliders 52 cooperate with the first linear guide rail 51. The first linear guide rail 51 is fixedly installed on the gantry frame 4, and multiple rails are arranged in parallel. A support body 411 is installed on the top of the gantry frame 4. The first servo motor 54 is fixed to the bottom of the support body 411. The output end of the first servo motor 54 passes upward through the support body 411 and is fitted with an active synchronous pulley 541. A pulley shaft 412 is rotatably mounted through the support body 411. A second lead screw 413 is fixed to the lower end of the pulley shaft 412, and a passive synchronous pulley 414 is fixed to the upper end of the pulley shaft 412. A synchronous toothed belt is installed between the stepping pulley 541 and the passive synchronous pulley 414. A second lead screw nut 531 that matches the second lead screw 413 is installed on the plate surface of the saw beam 53. The drive motor 57 is fixedly installed through the saw beam 53. The first band saw wheel 55 is installed at the output end of the drive motor 57. The tensioning device 6 is installed through the saw beam 53. The second band saw wheel 56 is rotatably installed through the tensioning device 6. A band saw 59 is installed between the first band saw wheel 55 and the second band saw wheel 56. The lower end of the nitrogen cylinder 58 is fixedly installed to the bed frame 1. A rotating seat 532 is installed on the plate surface of the saw beam 53. A connecting sleeve 533 is rotatably installed through the rotating seat 532. The movable end of the nitrogen cylinder 58 is inserted into the connecting sleeve 533 and fixed. A support device 7 for twisting the band saw 59 is also installed through the saw beam 53. Two support devices 7 are provided, corresponding to both sides of the processing table 2.
[0043] In the above technical solution, the design of nitrogen cylinder 58 is adopted to support the saw beam 53, reduce the force on the second lead screw 413, and also reduce the pressure on the first linear guide rail.
[0044] The tensioning device 6 can maintain the tension on the band saw 59. This tension is adjustable to ensure stable tension on the band saw.
[0045] See Figure 9 and Figure 10As shown, the tensioning device 6 includes a fixed base 61, which is fixed to the saw beam 53. Two upper and lower guide rails 62 are installed on the fixed base 61. A bearing 63 is slidably installed between the two guide rails 62. A rotating shaft is rotatably installed through the bearing 63. The second band saw wheel 56 is fixedly installed through the rotating shaft. A second servo motor 64 is installed through the fixed base 61. A screw 65 is installed at the output end of the second servo motor 64. The bearing 63 has a threaded hole 633 that mates with the screw 65.
[0046] In the above technical solution, the second servo motor 64 drives the screw 65 to rotate, thereby realizing the sliding of the bearing seat 63 and adjusting the tension of the band saw 59.
[0047] See Figure 5 , Figure 11 and Figure 12 As shown, the support device 7 includes a base structure 71. Four or more axles 72 are symmetrically arranged at the front and rear of the bottom of the base structure 71. The axles 72 are fixed to the base structure 71. Side pressure rollers 73 are mounted on the axles 72. An upper pressure roller 74 is rotatably installed on the side of the base structure 71. The band saw 59 passes between the side pressure rollers 73 on the front and rear sides. The upper pressure roller 74 is positioned above the band saw 59.
[0048] The function of the support device 7 is to twist the band saw 59 so that the cutting edge of the band saw 59 faces downward, so as to achieve high-speed sawing.
[0049] The function of the upper pressure roller 74 is to improve the stability of the band saw 59 when it is pressed down.
[0050] 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.
[0051] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values of the components and steps described in these embodiments do not limit the scope of this invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.
[0052] 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 (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.
[0053] 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.
[0054] 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 data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.
[0055] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. An aluminum material high-speed sawing band sawing machine, characterized by: The utility model provides a kind of sawing device, including bed frame (1), processing platform (2) is fixedly installed on the bed frame (1), clamping feeding device (3) is movably installed by the bed frame (1), the clamping feeding device (3) cooperates processing platform (2), gantry (4) is installed on the top of the bed frame (1), sawing assembly (5) is installed by the gantry (4), and the sawing assembly (5) is along the vertical sliding of the gantry (4);Wherein, the sawing assembly (5) includes first linear guide rail (51), first slider (52), saw beam (53), first servo motor (54), first band saw wheel (55), second band saw wheel (56), tensioning device (6), drive motor (57) and nitrogen cylinder (58);The first slider (52) is symmetrically provided with multiple, the first slider (52) is fixed with the saw beam (53), the first slider (52) cooperates the first linear guide rail (51), the first linear guide rail (51) is fixedly installed on the gantry (4), and multiple are parallelly arranged, support body (411) is installed on the top of the gantry (4), the first servo motor (54) is fixed to the bottom of the support body (411), the output end of the first servo motor (54) is installed with driving synchronous pulley (541) after being upwards through the support body (411), pulley shaft (412) is rotatably installed by the support body (411), the lower end of the pulley shaft (412) is fixed with second lead screw (413), the upper end of the pulley shaft (412) is fixed with passive synchronous pulley (414), synchronous toothed belt is installed between the driving synchronous pulley (541) and the passive synchronous pulley (414), the second lead screw nut (531) that cooperates the second lead screw (413) is installed on the board face of the saw beam (53), the drive motor (57) is fixedly installed by the saw beam (53), the first band saw wheel (55) is installed on the output end of the drive motor (57), the tensioning device (6) is installed by the saw beam (53), the second band saw wheel (56) is rotatably installed by the tensioning device (6);Band saw (59) is installed between the first band saw wheel (55) and the second band saw wheel (56), the lower end of the nitrogen cylinder (58) is fixedly installed with the bed frame (1), rotary seat (532) is installed on the board face of the saw beam (53), connecting sleeve (533) is rotatably installed by the rotary seat (532), and the movable end of the nitrogen cylinder (58) is inserted into the connecting sleeve (533) and fixed;Support device (7) for twisting band saw (59) is also installed by the saw beam (53), the support device (7) is provided with two, and two sides of processing platform (2) are corresponded respectively.
2. The aluminum high-speed sawing band sawing machine according to claim 1, characterized in that: The processing platform (2) includes a platform (21), a column (22) and an operating platform (26), the column (22) is supported on the bottom of the platform (21), the lower end of the column (22) is fixedly installed with the bed frame (1), the cover plate (23) is installed above the platform (21), a plurality of hollow grooves (24) are processed on the plate surface of the cover plate (23), the roller body (25) is rotatably installed in the platform (21), bearings are matched between the roller body (25) and the platform (21), part of the roller body (25) extends to the outside of the hollow groove (24), the operating platform (26) is installed on the top of the bed frame (1) and located in the front of the platform (21), the operating platform (26) and the platform (21) form a band saw slot (261) for the downward movement of the sawing assembly (5).
3. The aluminum high-speed sawing band sawing machine according to claim 2, characterized in that: The clamping feeding device (3) includes a linear guide rail (31), a sliding block (32), a servo motor (33), a first lead screw (34), a sliding table (35) and a clamping cylinder (36), the linear guide rail (31) is installed on the top of the bed frame (1) and located on both sides of the platform (21), the sliding block (32) is matched with the linear guide rail (31), the sliding table (35) is fixed on the top of the sliding block (32) by screws, the top of the sliding table (35) is processed with a passing groove (3555) passing through the platform (21), a plurality of clamping cylinders (36) are arranged on the left and right sides, the clamping cylinder (36) is installed on the top of the sliding table (35) and located on both sides of the passing groove (3555), the movable end of the clamping cylinder (36) is fixedly installed with a clamping plate (37), the height of the clamping plate (37) is higher than the height of the cover plate (23); the servo motor (33) is fixed on the top of the bed frame (1) and located below the platform (21), the first lead screw (34) is installed on the output end of the servo motor (33), the sliding table (35) has a first lead screw nut (321) matched with the first lead screw (34); the passing gap (371) corresponding to the band saw slot (261) is formed between two adjacent clamping plates (37) on the same side; the bearing (344) supporting the rotation of the first lead screw (34) is installed through the bed frame (1).
4. The aluminum high-speed sawing band sawing machine of claim 1, wherein: The tensioning device (6) includes a fixed seat (61), the fixed seat (61) is fixed with the saw beam (53), an upper guide rail (62) and a lower guide rail (62) are installed on the fixed seat (61), a shaft seat (63) is slidably installed between the two guide rails (62), a rotating shaft is rotatably installed through the shaft seat (63), the second band saw wheel (56) is fixedly installed through the rotating shaft, a second servo motor (64) is installed through the fixed seat (61), a screw rod (65) is installed on the output end of the second servo motor (64), the shaft seat (63) has a threaded hole (633) matched with the screw rod (65).
5. The aluminum high-speed sawing band sawing machine of claim 1, wherein: The supporting device (7) comprises a base structure (71), four or more wheel shafts (72) are symmetrically arranged at the bottom of the base structure (71), the wheel shafts (72) are fixed with the base structure (71), side pressing wheels (73) are assembled through the wheel shafts (72), upper pressing wheels (74) are rotatably installed at the side of the base structure (71), the band saw (59) passes between the side pressing wheels (73) from the front and rear sides, and the upper pressing wheels (74) are limited above the band saw (59).