Sander

Abstract

To improve a clamp mechanism in a sander.SOLUTION: A sander includes: a sanding portion having a planar sheet placement surface on which a sanding sheet can be placed; and a clamp mechanism capable of holding the sanding sheet in the sanding portion. The clamping mechanism includes: a clamp portion that is capable of holding the sanding sheet and is capable of sliding in a direction parallel to the sheet placement surface between a closed position at which the sanding sheet is held by a side surface of the sanding portion and an open position at which the sanding sheet can be removed; an elastic body that applies an urging force in a direction parallel to the seat placement surface, the urging force urging the clamp portion toward the closed position; and a holding mechanism capable of holding the clamp portion at the open position against the urging force. By releasing the holding of the clamp portion at the open position by the holding mechanism, the clamp portion can hold the sanding sheet.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to sanders. [Background technology]

[0002] A sander equipped with a clamp mechanism for holding a sanding sheet is known. Patent Document 1 describes a sander equipped with a torsion spring, a clamp lever, and a clamp member. A clamp lever is formed at one end of the torsion spring, and a clamp member is connected to the other end. When the clamp lever is engaged with a protruding engagement portion by a user while the torsion spring holds a biasing force, the clamp member holds the sanding sheet by the biasing force. Patent Document 2 describes a sander in which the clamp member is swung up and down by the user operating the clamp lever to hold and release the sanding sheet. The clamp member holds the sanding sheet by biasing the clamp member with the torsion spring. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-207964 A [Patent Document 2] Japanese Utility Model Application Publication No. 2-15256 Summary of the Invention [Problem to be solved by the invention]

[0004] In the sander described in Patent Document 1, when holding a sanding sheet, the user must lift the clamp lever against the biasing force of the torsion spring to engage the protruding engagement part. Therefore, when the user operates the clamp lever while holding the sanding sheet with his / her hand, the operability of the clamp lever is poor. In the sander described in Patent Document 2, the torsion spring and the clamp member swing up and down, so the structure of the clamp mechanism in the up and down direction becomes large.

[0005] The present disclosure aims to provide improvements regarding clamping mechanisms in sanders. [Means for solving the problem]

[0006] According to one non-limiting aspect of the present disclosure, a sander is provided that includes a sanding unit and at least one clamping mechanism. The sanding unit includes a planar sheet placement surface on which a sanding sheet can be placed. The at least one clamping mechanism can hold the sanding sheet on the sanding unit. The at least one clamping mechanism includes a clamping unit, at least one elastic body, and a holding mechanism. The clamping unit can hold the sanding sheet and can slide in a direction parallel to the sheet placement surface between a closed position in which the sanding sheet is held on a side surface of the sanding unit and an open position in which the sanding sheet can be removed. The at least one elastic body applies a biasing force that biases the clamping unit toward the closed position, the biasing force being in a direction parallel to the sheet placement surface. The holding mechanism can hold the clamping unit in the open position against the biasing force. The sander allows the clamping unit to hold the sanding sheet by releasing the holding of the clamping unit in the open position by the holding mechanism.

[0007] According to this aspect, when a user of the sander sets a sanding sheet on the clamp section held in the open position by the holding mechanism, and then operates the holding mechanism to release the clamp section from the open position, the force of the elastic body is added to the force of the user operating the holding mechanism, and the clamp section moves to the closed position. Thus, the sanding sheet can be held in the clamp section with a simple operation by the user. [Brief description of the drawings]

[0008] [Figure 1] FIG. [Diagram 2] FIG. 2 is a vertical cross-sectional view of the sander, illustrating an outline of the internal structure. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. 4 is an exploded perspective view illustrating a clamp mechanism. [Figure 6] FIG. [Figure 7] FIG. 4 is a side view showing a clamp lever. [Figure 8] FIG. 4 is a plan view showing the clamp mechanism and the base in a closed position. [Figure 9] FIG. 4 is a plan view showing the clamp mechanism and the base in an open position. [Figure 10] 13 is an explanatory diagram showing the relationship between a cam portion and a clamp member in a closed position state. FIG. [Figure 11] 13 is an explanatory diagram showing the relationship between the cam portion and the clamp member when the cam portion rotates in the opening direction from a closed position as a starting point. FIG. [Figure 12] 13 is an explanatory diagram showing the relationship between the cam portion and the clamp member in a maximum open state. FIG. [Figure 13] 13 is an explanatory diagram showing the relationship between the cam portion and the clamp member at the rotation stop position. FIG. [Figure 14] FIG. 2 illustrates the clamp mechanism in a closed position. [Figure 15]FIG. 2 illustrates the clamp mechanism in an open position. [Figure 16] 13 is an explanatory diagram showing a closed position state of a clamp mechanism using a rubber member as an elastic body. [Figure 17] 13 is an explanatory diagram showing an open position state of a clamp mechanism using a rubber member as an elastic body. [Figure 18] 13 is an explanatory diagram showing a closed position state of a clamp mechanism using a tension spring as an elastic body. [Figure 19] 13 is an explanatory diagram showing an open position state of a clamp mechanism using a tension spring as an elastic body. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] In a non-limiting embodiment of the present disclosure, the sander may include a long handle. When a direction perpendicular to the sheet placement surface is defined as a vertical direction and a direction in which the handle extends as viewed from the vertical direction is defined as a front-rear direction, the at least one clamping mechanism may include a front clamping mechanism disposed forward of a center of the sanding unit. The at least one clamping mechanism may include a rear clamping mechanism disposed rearward of a center of the sanding unit. According to this embodiment, the clamp mechanism is disposed in the same direction as the extension direction of the handle, which makes it possible to prevent the sander from becoming large in the left-right direction.

[0010] Additionally or alternatively, each of the at least one elastic body may be in the form of an elongated spring, the spring extending in a direction parallel to the seat placement surface. According to this embodiment, since the spring extends in a direction parallel to the seat arrangement surface, it is possible to prevent the clamp mechanism from becoming large in size in the vertical direction due to the spring.

[0011] Additionally or alternatively, each of the at least one elastic body may be in the form of an elongated compression spring. According to this embodiment, compared to a case where another spring such as a torsion spring is disposed as an elastic body in the clamp mechanism, it is possible to prevent the clamp mechanism from becoming large in size in the vertical direction.

[0012] In addition to or instead of the above embodiment, the holding mechanism may include a cam portion that rotates to come into contact with the clamp portion and press the clamp portion toward the open position. According to this embodiment, the holding mechanism includes a cam portion, so that a user of the sander can hold the clamp portion in the open position against the biasing force of the elastic body without exerting a large amount of force.

[0013] In addition to or instead of the above embodiment, when the rotational direction of the cam portion that presses the clamp portion toward the open position is defined as the opening direction, and the rotational direction of the cam portion that enables the clamp portion to slide to the closed position is defined as the closing direction, the holding mechanism may be provided with a stopper that stops the rotation of the cam portion in the opening direction at a position where the sliding width of the clamp portion in the direction toward the open position is at its maximum or where the sliding width exceeds its maximum and begins to decrease. According to this embodiment, the stopper can hold the clamp portion in the open position after it has been slid significantly, making it easy for the user to set the sanding sheet.

[0014] In addition to or instead of the above embodiment, the sanding unit may include at least one receiving portion for receiving the compression spring, and a length of each of the at least one receiving portion in a direction in which the compression spring extends may be shorter than a natural length of the compression spring. According to this embodiment, during the manufacturing process of the sander, when the compression spring is compressed and placed into the accommodating section, the compression spring presses against the inner wall of the accommodating section with its spring force, and the compression spring is fixed inside the accommodating section, thereby simplifying the manufacturing process of the sander.

[0015] In addition to or instead of the above embodiment, the clamp portion may be configured to cover an upper portion of the compression spring housed in the at least one housing portion. According to this embodiment, the compression spring can be protected from external factors.

[0016] In addition to or instead of the above embodiment, the holding mechanism may include a cam portion that rotates to come into contact with the clamp portion and press the clamp portion toward the open position. The holding mechanism may include a lever portion for controlling the rotation of the cam portion. An outer contour of the lever portion when the clamp portion is in the closed position may be configured to be located inside of an outer contour in a planar direction of the seat arrangement surface. According to this embodiment, when working with a sander, it is possible to prevent the outer casing of the lever portion from coming into contact with the workpiece or a wall portion rising from the workpiece.

[0017] In addition to or instead of the above embodiment, a suction unit may be provided for suctioning abrasive dust generated from the workpiece by sanding with the sander. A dust collection nozzle may be provided for discharging the suctioned abrasive dust to the rear side of the sander. The at least one clamping mechanism may include a rear clamping mechanism arranged rearward of the center of the sanding unit. The rear clamping mechanism may be arranged in a lower area of ​​the dust collection nozzle. The holding mechanism of the rear clamping mechanism may include a cam portion that rotates to come into contact with the clamping portion and press the clamping portion toward the open position. The holding mechanism of the rear clamping mechanism may include a lever portion for operating the rotation of the cam portion. The lever portion may have a portion that becomes higher in the upward direction as it moves away from the rotation axis of the cam portion. The highest portion of the lever portion may be at a height that does not contact the dust collection nozzle when the cam portion rotates. According to this embodiment, the cam portion can be rotated while effectively utilizing the area below the dust collection nozzle, thereby preventing the sander from becoming large overall.

[0018] An orbital sander according to a non-limiting embodiment of the present disclosure (hereinafter, also simply referred to as a sander 10) will be described below with reference to Figures 1 to 15. The sander 10 exemplified in this embodiment is also referred to as a finishing sander.

[0019] 1 and 2, the sander 10 includes a drive mechanism 60 having a drive shaft 66 (see FIG. 2), a housing 20 that accommodates the drive mechanism 60, a sanding unit 30 to which one end 661 of the drive shaft 66 is connected, and a grip 80 attached to the housing 20. Hereinafter, the central axis of the drive shaft 66 is also referred to as the drive axis A1.

[0020] The sander 10 further includes a handle 22 connected to the housing 20, and a battery attachment portion 50. The handle 22 extends in a direction intersecting the drive axis A1, with one end connected to the housing 20 and the other end configured as a free end.

[0021] In the following, the direction in which the drive shaft A1 extends is defined as the up-down direction of the sander 10, and in the up-down direction, the side where one end 661 of the drive shaft 66 is connected to the sanding unit 30 is defined as the lower side, and the opposite side is defined as the upper side. In addition, the direction in which the handle 22 extends when viewed from the up-down direction is defined as the front-rear direction of the sander 10. In the front-rear direction, the free end side of the handle 22 is defined as the rear side, and the opposite side is defined as the front side. Furthermore, the direction perpendicular to the front-rear direction and the up-down direction is defined as the left-right direction of the sander 10. In the left-right direction, the right side when viewed from the rear side to the front side is defined as the right side of the sander 10, and the opposite side is defined as the left side of the sander 10.

[0022] The housing 20 constitutes the outer shell of the sander 10. The front end of the housing 20 is configured as a grip attachment portion 100 to which the grip 80 is attached. In this embodiment, the grip 80 is configured to be detachable from the grip attachment portion 100.

[0023] As shown in Fig. 2, the drive mechanism 60 includes an electric motor 61. The drive mechanism 60 is configured to drive the sanding unit 30 by the rotational power of the electric motor 61. As shown in Fig. 2, in this embodiment, the electric motor 61 is a brushless motor. However, the electric motor 61 may be a motor with brushes.

[0024] The electric motor 61 includes a motor shaft 611 extending in the vertical direction, and a motor body 612 including a stator and a rotor. The motor shaft 611 is rotatably supported by bearings 62 and 63 fixed to the housing 20. The motor shaft 611 is disposed so as to be located at approximately the center of the sanding unit 30 when viewed in the vertical direction. The lower part of the motor shaft 611 is connected to a drive shaft 66. The drive shaft 66 is rotatably supported by bearings 62 and 63 fixed to the housing 20. The rotational power of the electric motor 61 is transmitted to the sanding unit 30 via the motor shaft 611 and the drive shaft 66. The rotational power of the electric motor 61 is reduced in speed by a known power transmission mechanism (not shown) and transmitted to the sanding unit 30. In this embodiment, the rotation axis of the motor shaft 611 coincides with the drive axis A1.

[0025] A fan 71 is attached around the drive shaft 66 below the bearing 63. The fan 71 sucks in the grinding dust generated from the workpiece by sanding with the sander 10. More specifically, the sheet placement surface 311 is provided with a communication hole communicating with the fan 71. The grinding dust generated from the workpiece by sanding with the sander 10 is sucked in through the communication hole. The storage space of the fan 71 communicates with the dust collection nozzle 72. The dust collection nozzle 72 extends rearward from the lower and rear ends of the housing 20. A cloth dust bag 82 for collecting dust is connected to the dust collection nozzle 72. The grinding dust sucked in by the fan 71 is discharged from the dust collection nozzle 72 and accumulates in the dust bag 82. In addition, a resin dust bag (not shown) or a hose (not shown) connected to a dust collector (not shown) can be attached to the dust collection nozzle 72.

[0026] As shown in FIG. 1 to FIG. 4, the sanding unit 30 is located at the bottom of the sander 10. The sanding unit 30 includes a pad 31 and a base 32. The sanding unit 30 is provided with a clamp mechanism 40 for clamping and fixing a sanding sheet. The pad 31 and the base 32 have a substantially rectangular shape with the longitudinal direction as viewed in the vertical direction. The base 32 is provided on the pad 31, and the two are connected by a bolt extending in the vertical direction. The clamp mechanisms 40 are provided on the front side and the rear side of the drive mechanism 60 on the base 32, one each. The clamp mechanism 40 provided on the front side of the base 32 and the clamp mechanism 40 provided on the rear side of the base 32 have the same configuration. As shown in FIG. 4, the clamp mechanism 40 provided on the rear side of the base 32 is provided in the lower region of the dust collection nozzle 72. Sanding paper (not shown) as a sanding sheet is attached to the sheet placement surface 311, which is the bottom surface of the pad 31, by using the clamp mechanism 40. The details of the clamp mechanism 40 will be described later.

[0027] As shown in FIG. 2, the sanding unit 30 is connected to the drive shaft 66 via a bearing 64. Specifically, a balancer 65 is fixed around the lower end of the drive shaft 66. The balancer 65 is fixed to the drive shaft 66 by a bolt that is screwed into a screw hole formed in the lower end of the drive shaft 66. The bearing 64 is sandwiched between the upper part of the balancer 65 and the base 32. The inner ring of the bearing 64 is supported by the lower part of the balancer 65. The bearing 64 is arranged in an eccentric state with respect to the drive shaft 66. The balancer 65 has a shape in which the center of gravity is offset in the opposite direction to the eccentric direction of the bearing 64 with respect to the drive shaft 66. This makes it possible to suppress the occurrence of vibration caused by the eccentricity of the bearing 64 with respect to the drive shaft 66.

[0028] The sanding unit 30 is connected to the housing 20 via four feet 73. The feet 73 are configured to suppress vibrations (especially vertical fluttering) associated with orbital motion. In this embodiment, the feet 73 are disposed near the four corners of the rectangular base 32. The feet 73 have a generally cylindrical shape extending in the vertical direction. The upper end of the foot 73 is engaged with the housing 20 via an O-ring. The lower end of the foot 73 is engaged with the base 32 via an O-ring. The foot 73 can be tilted in the vertical direction while squashing these O-rings.

[0029] The battery attachment section 50 is disposed on the front side of the handle 22. The battery attachment section 50 is configured so that a battery 55 serving as a power source for the electric motor 61 can be attached in a sliding manner in the front-rear direction. As shown in FIG. 2, when the battery 55 is attached to the battery attachment portion 50, In this case, the battery 55 is held above the sanding unit 30 and the motor shaft 611. At this time, the motor shaft 611 is located near the center of the battery 55 when viewed in the up-down direction.

[0030] As shown in Fig. 2, the controller 52 is accommodated in the housing 20. In this embodiment, the controller 52 is disposed behind the motor main body 612 and above the dust collection nozzle 72. The controller 52 is electrically connected to terminals of the battery attachment part 50 and to the electric motor 61. The controller 52 includes various circuits and is configured to control the operation of the electric motor 61 by controlling the power supplied from the battery 55 to the electric motor 61. Examples of the circuits include a high temperature protection circuit, an overcurrent protection circuit, and an overdischarge protection circuit.

[0031] 1, 2 and 4, a switch 25 is provided on the upper front end of the handle 22. The switch 25 is electrically connected to the controller 52. The switch 25 is provided for starting and stopping the electric motor 61.

[0032] <Clamp mechanism configuration> Next, the clamp mechanism 40 will be described with reference to Figures 1 to 15. First, the configuration of the clamp mechanism 40 will be described. After that, the function of the clamp mechanism 40 will be described.

[0033] As described above, the clamp mechanisms 40 are disposed above the base 32, one on the front side and one on the rear side across the drive mechanism 60. As shown in FIG. 5, the clamp mechanism 40 includes a cam lever 41, a clamp member 43, and a compression spring 45.

[0034] As shown in FIG. 5 to FIG. 9, the cam lever 41 includes a lever portion 412 and a cam portion 42. A through hole 414 is formed in the cam lever 41, which penetrates the cam portion 42. A screw 415 penetrates the through hole 414 and screws into a boss 321 formed in the base 32, thereby fastening the cam lever 41 to the base 32. The cam lever 41 can rotate around the boss 321 as a rotation axis. The boss 321 also functions as a cam shaft for the cam portion 42. The lever portion 412 functions as an operation portion for rotating the cam lever 41 by the user. The cam portion 42 has a function of converting a rotational motion into a linear motion. The cam portion 42 also has a function of converting a force applied from the outside into a rotational force that rotates the cam portion 42 itself. The cam portion 42 is accommodated in a cam accommodating portion 323, which is a bottomed hole formed in the base 32.

[0035] As shown in Fig. 5, the base 32 is formed with an elastic body accommodating portion 325 which is a bottomed hole. The compression spring 45 is accommodated in the elastic body accommodating portion 325 so as to extend in the front-rear direction. The length of the elastic body accommodating portion 325 in the front-rear direction is shorter than the natural length of the compression spring 45. In other words, the natural length of the compression spring 45 is longer than the length of the elastic body accommodating portion 325 in the front-rear direction. That is, the compression spring 45 is accommodated in the elastic body accommodating portion 325 in a compressed state.

[0036] The clamp member 43 is disposed on the upper part of the base 32. Specifically, the clamp member 43 is disposed between the cam lever 41 and the base 32 with respect to the up-down direction. In this embodiment, the clamp member 43 is formed by sheet metal cutting a metal plate-shaped member. The clamp member 43 is formed with a clamp upper surface portion 431, a spring contact portion 433, a cam contact portion 435, and a sheet contact portion 437.

[0037] The spring contact portion 433 is formed so as to extend downward from the clamp upper surface portion 431. As shown in Figs. 5, 14, and 15, the spring contact portion 433 is accommodated in the elastic body accommodating portion 325 and abuts against the compression spring 45. Therefore, the spring contact portion 433 is accommodated in the elastic body accommodating portion 325 in a state in which a biasing force is applied from the compression spring 45. In Figs. 14 and 15, the biasing force applied by the compression spring 45 to the spring contact portion 433 is indicated by an outlined arrow. Specifically, the spring contact portion 433 is applied with a biasing force from the compression spring 45 in a direction from the outside to the inside of the base 32 in the front-rear direction. More specifically, the spring contact portion 433 provided in the front clamp member 43 is applied with a biasing force from the compression spring 45 in a direction from the front side to the rear side. The spring contact portion 433 of the rear clamp member 43 receives a biasing force from the compression spring 45 in a direction from the rear side to the front side.

[0038] As shown in FIG. 14 and FIG. 15, the sheet contact portion 437 sandwiches the sanding sheet between the base 32 and the sheet contact portion 437. The sheet contact portion 437 is formed so as to extend downward from the clamp upper surface portion 431. Furthermore, the end portion of the sheet contact portion 437 is bent toward the side surface portion 327 of the base 32 to have a U-shape. The biasing force of the compression spring 45 applied to the spring contact portion 433 is transmitted to the sheet contact portion 437 via the clamp upper surface portion 431, and the sheet contact portion 437 presses the side surface portion 327 of the base 32. The sanding sheet is sandwiched by the force of the sheet contact portion 437 pressing the side surface portion 327 of the base 32.

[0039] 5, the cam contact portion 435 is formed so as to extend downward from the clamp upper surface portion 431, and is housed in the cam housing portion 323. The cam contact portion 435 abuts against the cam portion 42, and transmits the rotational force applied to the cam lever 41 by the user's rotational operation of the cam lever 41 to the clamp member 43 as a force in the front-rear direction.

[0040] The clamp upper surface portion 431 is configured to cover the compression spring 45 housed in the elastic body housing portion 325 on the upper side of the base 32. This configuration makes it possible to protect the compression spring 45 from external factors. Specifically, the clamp upper surface portion 431 makes it possible to prevent the compression spring 45 from directly contacting external tools, members, dust, liquids, and the like.

[0041] Next, the function of the clamp mechanism 40 will be described. Here, the position of the clamp member 43 capable of holding the sanding sheet, the position of the cam lever 41, and the position of the cam portion 42 as shown in Figures 8, 10, and 14 are defined as the "closed position." The state of the clamp mechanism 40 when the clamp member 43 is in the closed position is defined as the "closed position state." When the clamp mechanism 40 is in the closed position state, the sheet contact portion 437 abuts against the side portion 327, which is the side surface of the base 32.

[0042] 9, 13, and 15, the position of the clamp member 43, the position of the cam lever 41, and the position of the cam portion 42 at which the sanding sheet can be removed are defined as the "open position." The state of the clamp mechanism 40 when the clamp member 43 is in the open position is defined as the "open position state." When the clamp mechanism 40 is in the open position state, the sheet contact portion 437 is separated from the side portion 327, which is the side surface of the base 32.

[0043] A case where the cam lever 41 is rotated in the opening direction starting from the closed position will be described. As shown in FIG. 8, the lever portion 412 in the closed position extends in the left-right direction. When viewed from the top-down direction, the outer contour of the lever portion 412 in the closed position is located inside the outer contour in the planar direction of the sheet placement surface 311. More specifically, the outer contour of the lever portion 412 when the clamp member 43 is in the closed position is located inside the outer contours of the left and right side surfaces of the sheet placement surface 311. Therefore, when sanding work is performed with the sander 10, it is possible to prevent the outer contour of the lever portion 412 from coming into contact with the workpiece, the portion rising upward from the workpiece, or the wall portion. As a result, the user can sand even the corners of the workpiece.

[0044] As shown in Fig. 10, when the clamp mechanism 40 is in the closed position, a portion of the cam portion 42 corresponding to the minor axis abuts against the cam contact portion 435. The spring contact portion 433 receives a biasing force from the compression spring 45 in a direction from the outside toward the inside of the base 32 in the front-rear direction. In other words, the compression spring 45 applies a biasing force to the clamp member 43 that biases the clamp member 43 toward the closed position. In Fig. 10, the biasing force of the compression spring 45 is indicated by an outlined arrow.

[0045] As described above, the biasing force of the compression spring 45 applied to the spring contact portion 433 is transmitted to the sheet contact portion 437 via the clamp upper surface portion 431, and the sheet contact portion 437 presses against the side surface portion 327 of the base 32. The force of the sheet contact portion 437 pressing against the side surface portion 327 of the base 32 causes the clamp members 43 to clamp the sanding sheet. The clamp members 43 of the clamp mechanisms 40 arranged on both the front and rear sides of the base 32 clamp both ends of the sanding sheet in the front-rear direction, thereby fixing the sanding sheet to the sheet placement surface 311.

[0046] 14, a groove 328 extending in the left-right direction is formed in the side surface 327. When the clamp mechanism 40 is in the closed position, the end of the sheet contact portion 437 abuts against the groove 328 of the side surface 327. Therefore, in the closed position, the frictional force between the groove 328 and the sanding sheet held by the sheet contact portion 437 can increase the holding force of the sanding sheet by the clamp member 43 compared to a configuration in which the groove 328 is not formed in the side surface 327.

[0047] When the clamp mechanism 40 is to be shifted from the closed position to the open position, the user operates the lever portion 412 to rotate the cam lever 41 toward the outside of the base 32. Hereinafter, the rotation direction of the cam lever 41 from the closed position to the open position is defined as the opening direction, and the rotation direction of the cam lever 41 from the open position to the closed position is defined as the opening direction.

[0048] As shown in FIG. 11, when the cam lever 41 rotates in the opening direction, the cam portion 42 moves the cam contact portion 435 toward the outside in the front-rear direction of the base 32 while pressing the cam contact portion 435. The clamp member 43 slides in a direction parallel to the seat arrangement surface 311. As described above, the compression spring 45 applies a biasing force to the clamp member 43 that biases the clamp member 43 toward the closed position. As a result, the cam contact portion 435 of the clamp member 43 applies a pressing force toward the inside in the front-rear direction to the cam portion 42. Hereinafter, the pressing force toward the inside in the front-rear direction that the cam contact portion 435 applies to the cam portion 42 due to the biasing force of the compression spring 45 is defined as a pressing force PF.

[0049] The pressing force PF is converted by the cam portion 42 into a force in the rotational direction of the cam portion 42. Hereinafter, the force in the rotational direction acting on the cam portion 42 due to the pressing force PF is defined as a rotational force RF. In the state shown in FIG. 11, a rotational force RF in the closing direction acts on the cam portion 42. When the user rotates the cam lever 41 in the opening direction, the user rotates the cam lever 41 against the rotational force RF in the closing direction. Note that in FIG. 11, a circle corresponding to the orbit of the major axis when the cam portion 42 rotates is shown by a dashed line. The rotational force RF acts on the cam portion 42 as a force in the tangential direction of the dashed circle.

[0050] As shown in FIG. 12, when the cam portion 42 (cam lever 41) is further rotated in the opening direction, the clamp member 43 transitions to a state in which the sliding width in the direction toward the open position is maximum. In this state, the vector of the pressing force PF exists on a straight line connecting the contact point where the cam portion 42 abuts against the cam contact portion 435 and the cam shaft. Therefore, the pressing force PF with which the cam contact portion 435 presses the cam portion 42 is not converted into a rotational force RF that rotates the cam portion 42. Hereinafter, the state of the clamp mechanism 40 at this time is also referred to as a maximum open state. In addition, the positions of the clamp member 43, the cam lever 41, and the cam portion 42 in the maximum open state are defined as a maximum open position. In this embodiment, the cam lever 41 in the maximum open position can be further rotated in the opening direction.

[0051] 13, a stopper 324 is disposed in cam housing portion 323. Stopper 324 stops the rotation of cam portion 42 in the opening direction at a predetermined position. The position at which the rotation of cam portion 42 is stopped by stopper 324 is defined as the rotation stop position. In other words, when cam portion 42 is rotated in the opening direction starting from the closed position, cam portion 42 is positioned in the order of the closed position, the maximum open position, and the rotation stop position (open position).

[0052] In this embodiment, when the cam portion 42 (cam lever 41) is rotated in the opening direction, the stopper 324 stops the rotation of the cam portion 42 in the opening direction at a position where the sliding width of the clamp member 43 in the direction toward the open position exceeds the maximum and starts to decrease. With this configuration, even if the user releases the cam lever 41 from the rotation stop position, the cam lever 41 and the clamp member 43 can stably maintain the open position state. A specific description will be given below.

[0053] As described above, the cam portion 42 has a function of converting the pressing force PF by the cam contact portion 435 pressing the cam portion 42 into a rotational force RF that rotates the cam portion 42. The direction of the rotational force RF changes with the maximum opening position of the cam portion 42 as a boundary (changing point). More specifically, as shown in FIG. 11, when the cam portion 42 is located between the closed position and the maximum opening position, the pressing force PF by the cam contact portion 435 pressing the cam portion 42 is converted into a rotational force RF that rotates the cam portion 42 in the closing direction. On the other hand, as shown in FIG. 13, when the cam portion 42 is located between the maximum opening position and the rotation stop position, the pressing force PF by the cam contact portion 435 pressing the cam portion 42 is converted into a rotational force RF that rotates the cam portion 42 in the opening direction.

[0054] 13, a rotational force RF that rotates in the opening direction acts on cam portion 42 in the rotation stop position. Also, the rotation of cam portion 42 is stopped by stopper 324. As a result, even if the user releases cam lever 41 in the rotation stop position, a rotational force RF that rotates in the opening direction always acts on cam portion 42 in the rotation stop position, so that cam lever 41 and clamp member 43 can maintain the open position state.

[0055] In addition, since the rotational force RF that rotates the cam portion 42 in the rotation stop position always acts in the open direction, even if a force smaller than the rotational force RF that rotates the cam portion 42 in the open direction acts on the cam lever 41 from the outside, the cam lever 41 does not rotate in the closing direction, and the clamp mechanism 40 can maintain the open position state. More specifically, even if a rotational force in the closing direction smaller than the rotational force RF acts on the cam lever 41, the clamp mechanism 40 can maintain the open position state. That is, by adopting such a configuration, the clamp mechanism 40 can stably maintain the open position state. Note that the "open position state" in this embodiment is the state of the clamp mechanism 40 when the rotation of the cam portion 42 is stopped at the rotation stop position by the stopper 324 (rotation stop state).

[0056] Next, a case where the clamp mechanism 40 is moved in the closing direction starting from the open position state (rotation stop state) will be described. As shown in Fig. 15, when the clamp mechanism 40 is in the open position state, i.e., when the cam lever 41 (cam portion 42) is in the rotation stop position, a sufficient distance is ensured between the sheet contact portion 437 and the side portion 327 to insert a sanding sheet. After the sanding sheet is inserted between the sheet contact portion 437 and the side portion 327, the user operates the lever portion 412 to rotate the cam lever 41 in the closing direction, whereby the clamp member 43 slides to the closed position, and the end of the sanding sheet is clamped between the sheet contact portion 437 and the side portion 327 (groove portion 328).

[0057] As described above, the direction of the rotational force RF changes with the maximum open position of the cam portion 42 as the boundary (changing point). Specifically, when the cam portion 42 is located between the closed position and the maximum open position, the pressing force PF with which the cam contact portion 435 presses the cam portion 42 is converted into a rotational force RF that rotates the cam portion 42 in the closing direction. On the other hand, when the cam portion 42 is located between the maximum open position and the rotation stop position, the pressing force PF with which the cam contact portion 435 presses the cam portion 42 is converted into a rotational force RF that rotates the cam portion 42 in the opening direction. Therefore, when the user rotates the cam lever 41 at the rotation stop position in the closing direction, the cam lever 41 is rotated against the rotational force RF that rotates the cam portion 42 in the opening direction, which is acting on the cam lever 42, until the cam lever 41 rotates from the rotation stop position to the maximum open position. Then, when the user rotates the cam lever 41 in the closing direction and the rotation of the cam lever 41 passes the maximum open position, the direction of the rotational force RF changes, and the pressing force PF is converted into a rotational force RF that rotates the cam portion 42 in the closing direction. The rotational force RF in the closing direction acting on the cam portion 42 acts in addition to the force that the user applies to the cam lever 41 to rotate the cam lever 41 in the closing direction. Therefore, the user can rotate the cam lever 41 in the closing direction to the closed position with a small force.

[0058] Furthermore, as the cam lever 41 rotates in the closing direction beyond the maximum open position, the rotational force RF that rotates the cam portion 42 in the closing direction due to the pressing force PF with which the cam contact portion 435 presses the cam portion 42 increases. Therefore, when the user rotates the cam lever 41 in the closing direction beyond the maximum open position to a predetermined position, the cam lever 41 will then rotate to the closed position without the user applying any force. In this case, the spring constant of the compression spring 45 needs to be equal to or greater than a predetermined value. The function of the clamp mechanism 40 has been described above.

[0059] As described above, the sander 10 of this embodiment is provided with the cam lever 41 that can hold the clamp member 43 in the open position against the biasing force of the compression spring 45, so that the open position of the clamp member 43 can be maintained. As a result, the user's work of setting the sanding sheet in the clamp mechanism can be simplified.

[0060] When a user of the sander 10 places a sanding sheet on the clamp member 43 held in the open position by the cam lever 41 and then operates the cam lever 41 to release the clamp member 43 from the open position, the force exerted by the pressing force PF is added to the force exerted by the user in operating the cam lever 41 in the closing direction, and the clamp portion moves to the closed position. Thus, the sanding sheet can be held in the clamp portion with simple operation and little force by the user.

[0061] According to this embodiment, the clamp mechanisms 40 are disposed on the front and rear sides of the center of the sanding section 30, so that the sander 10 can be prevented from becoming large in the left-right direction.

[0062] According to this embodiment, as shown in Fig. 4, the clamp mechanism 40 disposed on the rear side of the base 32 is disposed in the area below the dust collection nozzle 72. The lever portion 412 has a portion that becomes higher in the upward direction as it moves away from the rotation axis of the cam portion 42. The highest portion of the lever portion, that is, the uppermost end 413 (see Fig. 7), is configured to have a height that does not contact the dust collection nozzle 72 when the cam portion 42 rotates. Therefore, the sander 10 can effectively utilize the area below the dust collection nozzle 72 while enabling the rotation of the cam portion 42, thereby preventing the sander 10 from becoming large overall.

[0063] According to this embodiment, the compression spring 45 extends in a direction parallel to the seat arrangement surface 311. Therefore, the compression spring 45 can prevent the clamp mechanism 40 from becoming large in the vertical direction.

[0064] Furthermore, according to this embodiment, the compression spring 45 is used as the elastic body. Therefore, compared to a configuration using other elastic bodies such as a torsion spring, it is possible to suppress an increase in size in the vertical direction.

[0065] According to this embodiment, the cam lever 41 (cam portion 42) is used as the holding mechanism. Therefore, the user of the sander 10 can hold the clamp member 43 in the open position against the biasing force of the compression spring 45 without exerting a large force.

[0066] According to this embodiment, the sander 10 includes a stopper 324 that stops the rotation of the cam portion 42 in the opening direction at a position (rotation stop position) where the sliding width of the clamp member 43 in the direction toward the open position is maximum (maximum open position) and the sliding width starts to decrease. Therefore, the stopper 324 can hold the clamp member 43 in a state where it has slid significantly to the open position, making it easy for the user to set the sanding sheet. In addition, even if the user releases the cam lever 41, the cam lever 41 and the clamp member 43 can maintain the open position state.

[0067] Furthermore, a rotational force RF that rotates the cam portion 42 in the rotation stop position in the open direction acts on the cam portion 42 in the rotation stop position. Therefore, the rotation of the cam portion 42 is stopped by the stopper 324. As a result, even if the user releases the cam lever 41 in the rotation stop position, the rotational force RF that rotates the cam portion 42 in the opening direction always acts on the cam portion 42 in the rotation stop position, so that the cam lever 41 and the clamp member 43 can maintain the open position state. Furthermore, since the rotational force RF that rotates the cam portion 42 in the opening direction always acts on the cam portion 42 in the rotation stop position, even if a force smaller than the rotational force RF that rotates the cam lever 41 in the opening direction acts on the cam lever 41 from the outside, the cam lever 41 does not rotate in the closing direction, and the clamp mechanism 40 can maintain the open position state. That is, by adopting such a configuration, the open position state of the clamp mechanism 40 can be stably maintained.

[0068] In this embodiment, the length of the elastic body accommodating portion 325 in the front-rear direction is shorter than the natural length of the compression spring 45. In other words, the natural length of the compression spring 45 is longer than the length of the elastic body accommodating portion 325 in the front-rear direction. That is, the compression spring 45 is accommodated in the elastic body accommodating portion 325 in a compressed state. Therefore, when assembling the clamp mechanism 40 in the manufacturing process of the sander 10, the compression spring 45 can be fixed in the elastic body accommodating portion 325 without using an assembly jig or the like. On the other hand, when a torsion spring is used in the clamp mechanism, an assembly jig is often required to assemble the spring in a compressed state. Compared to such a configuration, the manufacturing work of the sander 10 of this embodiment and the sander 10 itself can be simplified.

[0069] In this embodiment, the clamp upper surface portion 431 is configured to cover the compression spring 45 housed in the elastic body housing portion 325 on the upper side of the base 32. With this configuration, it is possible to protect the compression spring 45 from external factors. Specifically, the clamp upper surface portion 431 can prevent the compression spring 45 from directly contacting external tools, members, dust, liquids, and the like.

[0070] In the sander 10 of this embodiment, when viewed from the top and bottom, the outer contour of the lever portion 412 in the closed position is located inside the outer contour of the base 32. More specifically, when the clamp member 43 is in the closed position, the outer contour of the lever portion 412 is located inside the outer contour in the planar direction of the sheet placement surface 311. Therefore, when sanding work is performed using the sander 10, it is possible to prevent the outer contour of the lever portion 412 from coming into contact with the workpiece, parts rising upward from the workpiece, or wall parts. As a result, it is possible to sand even the corners of the workpiece.

[0071] The correspondence between each component (feature) of the above embodiment and each component (feature) of the present disclosure or invention is shown below. However, each component of the embodiment is merely an example and does not limit each component of the present disclosure or invention.

[0072] The sander 10 is an example of a "sander". The sanding paper is an example of a "sanding sheet". The sheet placement surface 311 is an example of a "sheet placement surface". The sanding section 30 is an example of a "sanding section". The clamp mechanism 40 is an example of a "clamp mechanism". The clamp mechanism 40 arranged forward of the center of the sanding section 30 is an example of a "front clamp mechanism". The clamp mechanism 40 arranged rearward of the center of the sanding section 30 is an example of a "rear clamp mechanism". The clamp member 43 is an example of a "clamp section". The compression spring 45 is an example of an "elastic body". The compression spring 45 is an example of a "spring". The handle 22 is an example of a "handle". The cam lever 41 is an example of a "holding mechanism". The cam portion 42 is an example of a "cam portion". The lever portion 412 is an example of a "lever portion". The stopper 324 is an example of a "stopper". The elastic body storage portion 325 is an example of a "storage portion". The fan 71 is an example of a "suction portion." The dust collection nozzle 72 is an example of a "dust collection nozzle."

[0073] <Other embodiments> Although several embodiments of the present invention have been described above, the above-mentioned embodiments are intended to facilitate understanding of the present invention and do not limit the present invention. The present invention may be modified or improved without departing from the spirit thereof, and the present invention includes equivalents thereof. In addition, any combination or omission of each form element described in the claims and specification is possible within the scope of solving at least a part of the above-mentioned problems or achieving at least a part of the effects.

[0074] In the above embodiment, the compression spring 45 is used as the elastic body, but other configurations may be used. For example, a rubber member having elastic force may be used as the elastic body. As shown in FIG. 16, a long rubber member 46 is disposed in the elastic body accommodating portion 325. The rubber member 46 applies a biasing force that biases the clamp member 43 toward the closed position in a direction parallel to the sheet placement surface 311. When the cam lever 41 is rotated from the closed position as a starting point to the open position, the rubber member 46 deforms inside the elastic body accommodating portion 325 as shown in FIG. 17 and applies a biasing force to the clamp member 43. The rubber member 46 has the same function as the compression spring 45 as an elastic body. Even if such a configuration is adopted, the same effect as the above embodiment can be obtained. In addition, the clamp mechanism 40 can be manufactured more inexpensively than the above embodiment.

[0075] In the above embodiment, the compression spring 45 is used as the elastic body, but other configurations may be used. For example, a tension spring may be used as the elastic body. As shown in FIG. 18, a long tension spring 47 is disposed in the elastic body housing 325. The position of the tension spring 47 in the elastic body housing 325 is different from that of the above embodiment. In this embodiment, the tension spring 47 is disposed in the elastic body housing 325, closer to the center of the base 32 than the spring contact portion 433. By disposing it in this manner, the tension spring 47 urges the clamp member 43 toward the closed position by tension (urging force). The tension acts in a direction parallel to the sheet placement surface 311. When the cam lever 41 is rotated from the closed position to the open position, it stretches inside the elastic body housing 325 as shown in FIG. 19, generating tension and applying a urging force to the clamp member 43. The rubber member 46 has the same function as the compression spring 45 as an elastic body. When tension spring 47 is used as the elastic body, one end of tension spring 47 needs to be fixed to elastic body accommodating portion 325 and the other end needs to be fixed to spring contact portion 433 .

[0076] In the above embodiment, a configuration may be adopted in which the pad 31 is not provided. In this case, the bottom surface of the base 32 functions as the "seat placement surface."

[0077] In the above embodiment, the sander 10 may have only one clamp mechanism 40. For example, the clamp mechanism 40 of this embodiment may be provided on the rear side of the base 32, and another clamp mechanism having a different configuration from the clamp mechanism 40 of this embodiment may be provided on the front side of the base 32. As the other clamp mechanism, a conventional clamp mechanism may be used. For example, a clamp mechanism using a torsion spring may be used.

[0078] A configuration in which the clamp mechanisms 40 are disposed on the left and right sides of the base 32 may be adopted. Also, a configuration in which the clamp mechanisms 40 are disposed on each of the front, rear, left and right sides of the base 32 may be adopted.

[0079] In the above embodiment, a configuration may be adopted in which the stopper 324 is disposed at a position where the rotation of the cam portion 42 in the opening direction stops at the maximum open position. When such a configuration is adopted, the stopper 324 can hold the state in which the clamp member 43 has been largely slid to the open position, making it easy for the user to set the sanding sheet. As another configuration, a configuration may be adopted in which the stopper 324 is disposed at a position where the rotation of the cam portion 42 in the opening direction stops at a predetermined position after the sliding width of the clamp member 43 in the direction toward the open position exceeds the maximum and the sliding width starts to decrease when the cam portion 42 (cam lever 41) is rotated in the opening direction. That is, in this sander, when the rotation direction of the cam portion that presses the clamp portion toward the open position is defined as the opening direction, and the rotation direction of the cam portion that allows the clamp portion to slide from the clamp portion to the closed position is defined as the closing direction, the holding mechanism may be configured to include a stopper that stops the rotation of the cam portion in the opening direction in a state after the sliding width of the clamp portion in the direction toward the open position exceeds the maximum and starts to decrease. When this configuration is adopted, the cam lever 41 and the clamp member 43 can be maintained in the open position even if the user releases the cam lever 41. In addition, since the clamp member 43 can be held in the open position by the stopper 324, it is possible to provide a configuration that makes it easy for the user to set the sanding sheet.

[0080] In the above embodiment, the clamp mechanism 40 may have only one elastic body. This can be achieved by disposing the elastic body near the center of the clamp mechanism 40, avoiding the cam portion 42.

[0081] In the above embodiment, the cam lever 41 is used as the holding mechanism, but other configurations may be used. For example, a rod-shaped member capable of holding the clamp member 43 in the open position against the biasing force of an elastic body may be disposed in the cam housing portion 323. When the clamp member 43 is moved to the open position, the rod-shaped member is interposed between the clamp member 43 (the portion corresponding to the cam contact portion 435) and the wall portion of the cam housing portion 323 and abuts against each member, and the rod-shaped member holds the clamp member 43 in the open position against the biasing force of the elastic body. By adopting such a configuration, the structure can be simplified.

[0082] The present disclosure is not limited to the above-mentioned embodiment and other embodiments, and can be realized in various configurations without departing from the spirit of the present disclosure. For example, the technical features in the embodiments corresponding to the technical features in each form described in the Summary of the Invention column can be appropriately replaced or combined to solve some or all of the above-mentioned problems or to achieve some or all of the above-mentioned effects. Furthermore, if the technical feature is not described as essential in this specification, it can be appropriately deleted. [Explanation of symbols]

[0083] 10: Sander, 20: Housing, 22: Handle, 25: Switch, 30: Sanding section, 31: Pad, 32: Base, 40: Clamping mechanism, 41: Cam lever, 42: Cam section, 43: Clamping member, 45: Compression spring, 46: Rubber member, 47: Tension spring, 50: Battery mounting section, 52: Controller, 55: Battery, 60: Driving mechanism, 61: Electric motor, 62: Bearing, 63: Bearing, 64: Bearing, 65: Balancer, 66: Driving shaft, 71: Fan, 72: Dust collection nozzle, 73: Hook , 80: grip, 82: dust bag, 100: grip attachment portion, 311: seat placement surface, 321: boss, 323: cam housing portion, 324: stopper, 325: elastic body housing portion, 327: side portion, 328: groove portion, 412: lever portion, 413: uppermost end, 414: through hole, 415: screw, 431: clamp upper surface portion, 433: spring contact portion, 435: cam contact portion, 437: seat contact portion, 611: motor shaft, 612: motor body portion, 661: one end of drive shaft, A1: drive shaft, PF: pressing force, RF: rotational force

Claims

1. A sanding unit having a flat sheet placement surface on which a sanding sheet can be placed; At least one clamp mechanism capable of holding the sanding sheet on the sanding section; Equipped with The at least one clamping mechanism comprises: a clamp portion capable of holding the sanding sheet and slidable in a direction parallel to the sheet placement surface between a closed position in which the sanding sheet is held on a side surface of the sanding portion and an open position in which the sanding sheet can be removed; at least one elastic body that applies a biasing force to the clamp portion toward the closed position in a direction parallel to the seat arrangement surface; a holding mechanism capable of holding the clamp portion in the open position against the biasing force; Equipped with The holding mechanism releases the clamp portion from the open position, thereby allowing the clamp portion to hold the sanding sheet. Sanda.

2. 2. The sander according to claim 1, Equipped with a long handle, When the direction perpendicular to the seat arrangement surface is defined as the up-down direction, and the direction in which the handle extends as viewed from the up-down direction is defined as the front-rear direction, The at least one clamping mechanism comprises: a front clamp mechanism disposed forward of the center of the sanding unit; A rear clamp mechanism disposed rearward of the center of the sanding unit; Includes Sanda.

3. The sandal according to claim 1 or 2, Each of the at least one elastic body is in the form of an elongated spring; The spring extends in a direction parallel to the seat arrangement surface. Sanda.

4. The sandal according to claims 1 to 3, Each of the at least one elastic body is in the form of an elongated compression spring. Sanda.

5. The sandal according to any one of claims 1 to 4, The holding mechanism includes: A cam portion is provided which rotates to come into contact with the clamp portion and press the clamp portion toward the open position. Sanda.

6. 6. The sander according to claim 5, When the rotation direction of the cam portion that presses the clamp portion toward the open position is defined as an opening direction, and the rotation direction of the cam portion that allows the clamp portion to slide to the closed position is defined as a closing direction, The holding mechanism includes: a stopper that stops the rotation of the cam portion in the opening direction at a position where the sliding width of the clamp portion in the direction toward the open position is at a maximum or where the sliding width exceeds the maximum and starts to decrease; Sanda.

7. 5. The sander according to claim 4, The sanding section includes at least one receiving section for receiving the compression spring, A length of each of the at least one housing portion in a direction in which the compression spring extends is shorter than a natural length of the compression spring. Sanda.

8. 8. The sander according to claim 7, The clamp portion is The compression spring is configured to cover the upper part of the compression spring housed in the at least one housing portion. Sanda.

9. The sandal according to any one of claims 5 to 8, The holding mechanism includes: a cam portion that rotates to come into contact with the clamp portion and press the clamp portion toward the open position; a lever portion for controlling the rotation of the cam portion, When the clamp portion is in the closed position, the outer contour of the lever portion is located inside the outer contour of the seat arrangement surface in the planar direction. Sanda.

10. The sandal according to any one of claims 5 to 9, A suction unit that sucks up abrasive debris generated from the workpiece by sanding with the sander; a dust collection nozzle that discharges the sucked abrasive debris to the rear side of the sander; Equipped with The at least one clamping mechanism includes a rear clamping mechanism disposed rearward of a center of the sanding unit, the rear clamp mechanism is disposed in a lower region of the dust collection nozzle, The holding mechanism of the rear clamp mechanism includes: a cam portion that rotates to come into contact with the clamp portion and press the clamp portion toward the open position; a lever portion for controlling the rotation of the cam portion, the lever portion has a portion that becomes higher in an upward direction as it becomes farther from the rotation axis of the cam portion, The highest part of the lever portion is at a height such that the lever portion does not come into contact with the discharge nozzle when the cam portion rotates. Sanda.

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