Abstract: A strainer is provided for a snare drum having a bottom drumhead. The strainer includes a mounting bracket configured to be mounted to a side of a drum shell near the bottom drumhead. A slider is received in an opening in the mounting bracket for vertical movement with respect to the mounting bracket. The slider has an adjustment/tension knob including a threaded bolt. The mounting bracket has a portion configured to clamp on a portion of the slider. A key bolt structure is configured to releasably cause clamping of the mounting bracket against the slider. A post has a portion received in an internal opening of the slider threadedly engaged with the bolt. A snare carrier is fixed to the post. The snare carrier is configured to receive and carry an end of a snare wire assembly.

Abstract: A snare adjustment device includes a snare protection frame having snares connected thereto, a holding body, a slider slidably connected to the holding body and moving the snare protection frame and the snares along with it, a switch member, and a manual lever. The switch member includes a latch section movable by a push section to engage with or disengage from the slider, such that the slider is stopped from or allowed to move, respectively. The manual lever is pivotally connected to the holding body and can be swung up and down for moving the slider. The manual lever includes a lever section, which and the push section of the switch member are protruded beyond a reference side of the holding body. Therefore, a drum player can hit the push and the lever section with a drum stick to quickly switch the snares between a tightened and a loosened state.

Abstract: A strainer device for a drum includes a fixing portion attachable to a shell of the drum, an operation portion, a movable portion moved with respect to the fixing portion to change a snare wire between an ON state and an OFF state, a pressing member, a cam portion including a cam surface, and a follower configured to be relatively displaced with respect to the cam portion between a first position and a second position in the cam portion while the pressing member is pressing against the cam surface. A direction of a force acting on the follower with respect to the cam portion is directed to: a side of the first position within the cam portion in a state where the follower is disposed in the first position, and a side of the second position in a state where the follower is disposed in the second position.

Abstract: The present invention provides a drum snare including a fixed seat, an actuation column, an actuation handle, a pull-down seat, an adjustment bolt, and a packing assembly. The actuation handle passes through a lateral hole to connect and fix to the actuation column. The lateral hole includes two snap-in slots pressing against the actuation handle. The pull-down seat includes a clamping seat and a non-circular rod body passing through the fixed seat in a non-rotation manner. The non-circular rod body includes an internal thread hole. The adjustment bolt is rotatably fixed on the actuation column. The adjustment bolt includes a thread section penetrating in the internal thread hole. The packing assembly is provided between the adjustment bolt and the actuation column. Therefore, a friction force between the adjustment bolt and the actuation column is increased through the packing assembly, and looseness of the adjustment bolt can be avoided.

Abstract: A pot call for producing turkey sounds includes: having separate sound chambers, having a top pot shape on the top, a top open end, a top side wall, a top closed end, a top sound hole aperture or a plurality of top sound hole apertures, having the top open end covered by a top playing surface forming a top sound chamber; and having a bottom pot shape on the bottom, a bottom open end, a bottom side wall, a bottom closed end, a bottom sound hole aperture or a plurality of bottom sound hole apertures, having the bottom open end covered by a bottom playing surface forming a bottom sound chamber. In use a striker is dragged across either the top playing surface or the bottom playing surface creating a turkey sound.

Abstract: An effect imparter for a musical instrument includes a wire bundle including at least one snare, and a plate that has a hook configured to be hooked by a string and that is fixed to a first end portion of the wire bundle.

Abstract: A snare drum including a self-alignment component is disclosed. The self-alignment component may be engaged by a tensioning band, which can attach to one end of a snare that contacts or is proximate a bottom drum head. The tensioning band may loop around a part of the self-alignment component, such as an alignment piece thereof. The geometry of the self-alignment component is designed to allow the tensioning band to self-align such that portions on opposing sides of the alignment piece have approximately equal tension therein and/or have approximately equal length, thus allowing for a properly aligned snare on the bottom drum head. The self-alignment component can include a plate portion attached to a drum sidewall or tensioning device on a drum sidewall, and can further include a cover portion for attachment to the plate portion.

Abstract: A percussion instrument, includes a Cajon body including a front striking surface, a floating snare assembly positioned at a portion of the front striking surface, and at least one connector connecting the Cajon body and the floating snare assembly. The floating snare assembly includes at least one snare wire contacting the front striking surface.

Abstract: A snare system for use with a drum has a snare assembly with snares extended longitudinally between opposite end plates. The end plates define a slot from a top surface to a bottom surface with obliquely extending walls. Two connectors, each with a strap carrying a latch member, are attached to opposite sides of the drum via its strap with latch member within the drum rim. Each latch member includes a flange with oblique configuration complimentary to the oblique slot in the end plates. The snare assembly is attached via sliding engagement of the respective flanges into the respective slots with the surfaces of each in surface-to-surface contact so that the connectors maintain the snare assembly attached to the drum. The snare assembly is removable quickly by reverse sliding of the flanges from the slots to interchange with a different snare assembly having end plates with a common configuration.

Abstract: A snare drum includes a tension adjusting device fixed to a strainer. The tension adjusting device includes a moving member that moves in a direction intersecting inner sound wires of the snare wire. A user can adjust tension of the snare wire by operating the tension adjusting device to cause the moving member to displace the inner sound wires.

Abstract: A versatile cajón having a compact footprint that incorporates actuators for an internal bass-beater and an external hi-hat. The cajón may further serve as a base for supporting additional percussive instruments, such as snare drums, tom drums, cymbals, and Latin percussion. In an embodiment, a bass drum pedal may be secured inside the cajón and having a rotating shaft protruding through a side wall of the cajón. The shaft protrusion may be coupled to a foot pedal in an actuating manner. As such, when a percussionist presses down on the foot pedal (e.g., with a foot action), the shaft rotates the beater head to strike an internal wall of the cajón, thereby producing a bass-like percussive sound. Similarly, the system may include a hi-hat pedal and shaft combination that is also attached directly to one or more external side walls of the cajón.

Abstract: A strainer assembly is provided for a snare drum having a shell and a bottom drumhead. The strainer assembly comprises a plurality of snare wires, a frame, a control mechanism, and a throw-off mechanism. Both ends of the snare wires are connected to the frame. The control mechanism includes a slidable part connected to a first end of the frame and a first button for controlling the vertical movement of the slidable part. The throw-off mechanism includes a slidable lower part connected to a second end of the frame and a second button for controlling the vertical movement of the slidable lower part.

Abstract: A snare wire is attached to a snare drum using a snare frame. A string made of flexible material is employed as a coupling member for coupling the snare frame to the snare drum. In the state in which the snare wire is attached to the snare drum by means of the snare frame, frame end sections of the snare wire are each arranged outward with respect to the outer peripheral edge of the back-surface head.

Abstract: An adjustable drum snare kit includes a stretcher panel holding replaceable strands of beads or wire which cooperatively engage a snare drum together with a tool for adjusting the tension of the stretcher panel and snare drum strands held thereby enabling quick replacement of individual strands for repair or performance reasons.

Abstract: The present disclosure relates, in one embodiment to a multimedia display apparatus. The multimedia display apparatus may comprise a housing which may be connected to a chassis. The chassis may be configured to attach to the underside of a music drum via a biasing element, thereby positioning the housing so as to project a multimedia image onto the head of the music drum. A multimedia projector may be disposed inside the housing and configured to project a multimedia image through the open bottom or transparent surface of the music drum and displayed on the top surface of the white or translucent drumhead.

Abstract: A snare wire includes a snare and a pair of attachment tools fixed to opposite end sections of the snare. Each of the attachment tools includes a bonding portion with which the snare is bonded, a catching portion that catches a strap or a cord, and a pressing portion that contacts the strap or the cord caught by the catching portion and is pressed in a direction separating from a drum head. The catching portion is arranged at a position between the center of the drum head and the pressing portion and below the bonding portion.

Abstract: A strainer system includes an adjustable slide assembly that can be used as a strainer side assembly or a butt side slide assembly for tensioning a snare that will not detune due to sympathetic vibrations. The strainer system may also be configured to easily control the amount of snare contact with the bearing edge on both the strainer side and the butt side of the shell body.

Abstract: A snare drum having an improved throw off includes a strainer shaft and a strainer bar both extending through the interior of the drum shell. The strainer bar is linked to the strainer shaft, a snare assembly is connected to the strainer bar, and a handle rotates the strainer shaft which moves the strainer bar and snare assembly between an upper position in which the snares of the snare assembly are engaged with the bottom head of the drum, and lower position in which the snares are disengaged from the bottom head. The snares are in parallel relation to the bottom head of the drum throughout the range of movement between the upper and lower positions. In one embodiment, the drum comprises a wood laminate and the top and bottom shell caps comprise carbon fiber.

Abstract: A strainer is provided for a snare drum having a bottom drumhead. The strainer includes a snare assembly including a snare carrier and a plurality of snares coupled therewith. A throw-side component includes a bracket member releasably mounted to the snare drum and a slide member moveable relative to the bracket member and engaging the snare carrier. The slide member includes a slider handle fixed thereto and a locking toggle such that when the strainer is coupled to the snare drum, manual movement of the slider handle causes the snares to move toward the bottom drumhead, with the locking toggle being constructed and arranged to be 1) moved to a first, locking position engaging the bracket member so as to lock the slide member to the bracket member, and 2) moved to a second, release position releasing the slide member from engagement with the bracket member.

Abstract: A snare cajón percussion instrument is disclosed. The instrument comprises a closed frame body having a plurality of sides, each side having a top portion, a bottom portion, an inner portion, and an outer portion. A rigid striking surface is securely affixed to the top portions of the plurality of sides. A snare apparatus having a brace, a fastener, and at least one snare element is securely attached to the inner portion of a first side of the frame body via the fastener and is configured to allow the snare element to alternatively contact and not contact the striking surface to produce a snare sound. The instrument may have a second striking surface that does not contact the snare apparatus and produces a cajón sound.

Abstract: A percussive shaker instrument with improved control in producing rhythmic sound and capable of producing different percussive sounds in a single shaker is disclosed. The shaker comprises one or more channels filled with a striker material. The channel isolates the striker material from the striker material in other channels and from any other part of the shaker. The striker material is freely movable within the channel such that it may collide with a striking surface when the shaker is moved.

Abstract: A tension adjustment hoop (1) for tensioning a resonant skin (13) on a musical instrument (6, 25), the tension adjustment hoop (1) being formed by a ring (2) with a center axis (3) and with retention means (4) arranged to interact with coupling means (5) on the musical instrument (6, 25) for retention of the tension adjustment hoop (1), the tension adjustment hoop (1) having an opposing top side (7) and bottom side (8), where the tension adjustment hoop (1) comprises an inner fluid channel (17), provided with a pressure adjustment connection (26) in hydraulic connection with the fluid channel (17), and a plurality of pistons (10), each in hydraulic connection with the fluid channel (17), each with a free end (11) opposite the fluid channel (17), and each, under the influence of the pressure in the fluid channel (17), being displaceable in a direction parallel to the center axis (3) of the tension adjustment hoop (1) between a first extreme position, where the free end (11) is within or level with the bottom s

Abstract: A snare assembly tensioning and locking mechanism for holding snare wires in either a contact or non-contact position against a bottom drum head of a snare drum. The mechanism uses a lever mounted horseshoe shaped clip including surface bumps or protrusions that, when the lever is in an upward and locked position, engage a set of complementary notches on a surrounding peripheral surface of a snare wire tension adjusting knob. In alternate embodiments, the locking lever may pivot toward the drum or in a direction tangential to the drum. In this manner, the snare wires are held in tension against inadvertent loosening of the tension adjusting knob while the drum is played.

Abstract: A percussion instrument includes at least one pad and a support frame supporting the pad. The support frame includes a central vertical frame, a left vertical frame located in a left rear direction of the central vertical frame when viewed from the player side, a right vertical frame located in a right rear direction of the central vertical frame when viewed from the player side, a left transverse frame extending between the central vertical frame and the left vertical frame and connecting the central vertical frame with the left vertical frame, and a right transverse frame extending between the central vertical frame and the right vertical frame and connecting the central vertical frame with the right vertical frame. The at least one pad is connected with the central vertical frame.

Abstract: An adjustment assembly for snare wires includes an adjustment unit and a pressing unit respectively located on two opposite positions of the shell of a snare drum. The adjustment unit has a body with a slide slot. A shifting member is slidably connected to the body and driven by a driving member connected to the body. The shifting member has a wire carrier which is adjusted by rotating an adjusting bolt. The pressing unit includes another wire carrier which is controlled by another adjusting bolt. By adjustment of the two adjustment bolts, the tension of the snare wires can be adjusted.

Abstract: A cymbal pickup is described, including a sensor detecting the vibration of the cymbal, and a sensor attaching part to which the sensor is attached. The cymbal has, through its center, a hole that allows a rod to be inserted through. The sensor attaching part includes: a first abutting part having a first insertion hole for pass of the rod, a second abutting part configured opposite to a side of the first abutting part and having a second insertion hole for pass of the rod, and an insertion part between the two abutting parts to maintain a separation distance between the opposite sides of the two abutting parts. The sensor is attached to a side of the first or the second abutting part. The cymbal pickup abuts the cymbal and is fixed together with the cymbal to detect its vibration while the rod is inserted through them.

Abstract: A percussion instrument includes at least one pad and a support frame supporting the pad. The support frame includes a central vertical frame, a left vertical frame located in a left rear direction of the central vertical frame when viewed from the player side, a right vertical frame located in a right rear direction of the central vertical frame when viewed from the player side, a left transverse frame extending between the central vertical frame and the left vertical frame and connecting the central vertical frame with the left vertical frame, and a right transverse frame extending between the central vertical frame and the right vertical frame and connecting the central vertical frame with the right vertical frame. The at least one pad is connected with the central vertical frame.

Abstract: The present invention generally relates to cajón drums. Specifically, this invention relates to a multi-tonal box drum kit that provides a form factor that is easy and convenient to use while producing the tones and sounds of a full drum kit or some subset thereof.

Abstract: A snare drum 10 has a hollow cylindrical shell 11, a batter head 12 mounted on one end of the shell 11, a snare side head 13 mounted on the other end of the shell 11 and a snare wire 14 whose both ends are held by the both sides of the shell 11 to span across the surface of the snare side head 13. The snare side head 13 has a plurality of through-holes 13c. As a result, the snare drum 10 reduces sound volume while maintaining natural timbre and feeling of striking a snare drum.

Abstract: A percussion instrument of the type having a box composed of four walls (1) forming the outline, on which a top (2) rests, the lateral end walls (3-4) having a rectangular profile, the front (5) and rear (6) faces having a convex profile (7) in their lower part whilst in their upper part on which the top rests they follow a line which is firstly rectilinear (8), then continued by a concave part (9), which is itself continued by a rectilinear or very slightly convex part (10), such that the box is divided into three zones: a deep zone (8) for producing bass sounds, continued by a shallower median part (9) for producing middle register sounds, the median part itself being continued in such a way as to form a chamber (10) which is slightly deeper than the median part for producing high pitched sounds, the chamber (10) producing the high pitched sounds being provided with a snare (17) lying against the top.

Abstract: The modular throw assembly disclosed herein comprises a plurality of throws comprising lever arms positionably mounted upon a single shaft. In one form, the lever arms are allowed to slide longitudinally along a portion of the shaft while the lever arms are in the released position, but are may be less likely to be longitudinally repositioned when in the tensioned position as the tension of the snare set will produce sufficient friction to hinder longitudinal sliding. In other embodiments, a setscrew or other component may be utilized to fix the position of each lever arm along the axis of the shaft. In another embodiment, narrow or wide spacers may alternatively be provided between each adjacent lever arm to provide this spacing between adjacent lever arms.

Abstract: A set of snares for a drum comprising an elongated first wire with two ends to be placed at least in part against a surface of a head of the drum and a first and one second fastening means for fastening the set of snares to the snare drum, wherein the first end of the first wire is attached to the first fastening means and the second end of the first wire is attached to the second fastening means, wherein the first wire runs between the two fastening means, wherein the first wire is shaped such that, at least along a partial section of the first wire, it follows an envelope body, the outer dimensions of which in the assembled state of the set of snares on the drum vary in a plane extending from the first fastening means to the second fastening means and intersecting the surface of the head of the drum.

Abstract: A set of snares for a drum comprising an elongated first wire with two ends to be placed at least in part against a surface of a head of the drum and a first and one second fastening means for fastening the set of snares to the snare drum, wherein the first end of the first wire is attached to the first fastening means and the second end of the first wire is attached to the second fastening means, wherein the first wire runs between the two fastening means, wherein the first wire is shaped such that, at least along a partial section of the first wire, it follows an envelope body, the outer dimensions of which in the assembled state of the set of snares on the drum vary in a plane extending from the first fastening means to the second fastening means and intersecting the surface of the head of the drum.

Abstract: A snare strainer adapted to a snare drum is equipped with two strainers, which are attached to the opposite positions on the circumferential exterior of a cylinder of the snare drum and which control a snappy member to be selectively brought into contact with or separated from the backside head opposite to the drumhead. Herein, a moving base vertically moves along a fixed base attached to the circumferential exterior of the cylinder; holding members, which are tightly joined together so as to hold the terminal of the snappy member, are supported by a support member fixed to the moving base. The holding members are engaged with the support member due to a magnetic attraction exerted by permanent magnets. This makes it possible for the person to detachably attach the holding members to the support member without using tools; hence, it is possible to improve the handling of the snare strainer.

Abstract: A snare band adjustment and locking device of a snare drum includes a mechanism for adjusting first, second and third settings, a first setting wherein the snare band is removed from the snare head, a second setting wherein the snare band has a maximum, predetermined contact pressure with the snare head, and a third setting wherein the contact pressure of the snare band with the snare head can be continuously varied between the contact pressure in the first and second settings. The adjustment mechanism is operated in the third setting via a foot pedal and a cable running through a control member which determines by its tension the spacing between the control member and a control lever pretensioned by a compression spring.

Abstract: A drum having a resonant chamber for producing a range of sounds and at least one device for allowing the sound so produced to be altered, which includes a plurality of internal snares which can be brought into contact with the internal surface of the external surface of the resonant chamber which is struck by the player. The drum may also include a bass drum stick mounted within the chamber and adapted for movement to be able to selectively strike the inner surface of the drum which is struck by the player. The bass drum stick may include a pedal, or other device, operable by the player and external to the drum for effecting movement of the bass drum stick.

Abstract: A snare drum having four cylindrical members which nest within and are permanently attached to each other from the top shell of the drum. The top ends of the four cylindrical members are located adjacent to each other and the bottom ends of the third and fourth cylindrical members are located below the bottom ends of the first and second cylindrical members. A fifth cylindrical member slides axially along the lower end of the third cylindrical member. The top ends of the four cylindrical members are covered by a first drum head and the bottom ends of the third and fourth cylindrical members are covered by a second drum head. The four cylindrical members are the top shell for the drum and the fifth cylindrical member is the bottom shell for the drum. The distance between the first and second drum heads change as the fifth cylindrical member is manually moved axially along the third cylindrical member.

Abstract: The invention relates to a snare tension device for tensioning and releasing a snare wire. In the snare tension device a rotation movement of a rotation element is transferred to a pushing element by means of a transfer element.

Abstract: Wherein a cajon incorporating a rattle system is attached to the front panel of the cajon, provision is made that the rattle system give off a more desirable musical rattle or buzzing sound then any prior art as the cajon is played by a percussionist. With the rattle system mounted and in place, it's hollow body allows free moving glass beads to be set into motion creating a much desired audible response upon impact of the front face of the cajon. Further, this audible response is a controlled or gated response due to the way the glass beads travel up an incline within the rattle assembly and then return to their relative starting positions leaving no lingering rattle or buzzing sound.

Abstract: A snare drum having four cylindrical members which nest within and are permanently attached to each other from the top shell of the drum. The top ends of the four cylindrical members are located adjacent to each other and the bottom ends of the third and fourth cylindrical members are located below the bottom ends of the first and second cylindrical members. A fifth cylindrical member slides axially along the lower end of the third cylindrical member. The top ends of the four cylindrical members are covered by a first drum head and the bottom ends of the third and fourth cylindrical members are covered by a second drum head. The four cylindrical members are the top shell for the drum and the fifth cylindrical member is the bottom shell for the drum. The distance between the first and second drum heads change as the fifth cylindrical member is manually moved axially along the third cylindrical member.

Abstract: The present invention relates to a percussion instrument of the type consisting of a box composed of four walls (1) forming the outline, on which a top (2) rests, the lateral end walls (3-4) having a rectangular profile, the front (5) and rear (6) faces having a convex profile (7) in their lower part whilst in their upper part on which the top rests they follow a line which is firstly rectilinear (8), then continued by a concave part (9), which is itself continued by a rectilinear or very slightly convex part (10), such that the box is divided into three zones: a deep zone (8) for producing bass sounds, continued by a shallower median part (9) for producing middle register sounds, said median part itself being continued in such a way as to form a chamber (10) which is slightly deeper than the median part for producing high pitched sounds, the chamber (10) producing the high pitched sounds being provided with a snare (17) lying against the top.

Abstract: A strainer includes a strainer body, a slider to which a cam follower is fixed, a holder to which snare wires are fixed, an operating lever, and a cam that is pivoted through operation of the operating lever. The slider is slid relative to the strainer body by pivoting the cam through operation of the operating lever so that the cam follower moves along the cam surface. The movement distance of the slider linearly changes with respect to an operation angle of the operating lever.

Abstract: Intended is to provide a strainer having a switch mechanism, which is hardly rattled by a wear, which can be stably operated by a weak force, which does not load a snare assembly and which can maintain an excellent operation feel, and a snare assembly holding structure which has a reliable clamping force so that it can prevent the looseness of the snare assembly end portion. An operation lever is hinged on its base end side to a base body. A link is turnably connected on its one end side to the lower side portion of a snare assembly holding member, and is likewise turnably connected on its other end side to a midway position of the operation lever. When the operation lever turns upward, the snare assembly holding member is pulled upward through the link. When the operation lever turns downward, the snare assembly holding member is pushed downward.

Abstract: In combination with a snare drum having snare wires, a drum head and a side wall, slidable bands endwise connected with the wires, first adjustable mechanism connected with the band ends, and support by the wall, second adjustable mechanism connected with another band end, and supported by said wall, whereby adjustment of either or both of the mechanism tensions at least one band, and said snare wires.

Abstract: A snare strainer adapted to a snare drum is equipped with two strainers, which are attached to the opposite positions on the circumferential exterior of a cylinder of the snare drum and which control a snappy member to be selectively brought into contact with or separated from the backside head opposite to the drumhead. Herein, a moving base vertically moves along a fixed base attached to the circumferential exterior of the cylinder; holding members, which are tightly joined together so as to hold the terminal of the snappy member, are supported by a support member fixed to the moving base. The holding members are engaged with the support member due to a magnetic attraction exerted by permanent magnets. This makes it possible for the person to detachably attach the holding members to the support member without using tools; hence, it is possible to improve the handling of the snare strainer.

Abstract: A drum assembly includes a first drum assembly positioned above a second drum assembly in a spaced apart relationship, where the bottom of the first drum assembly is positioned above the second drum assembly. Sound waves emanated from a playing surface of the first drum assembly impact a playing surface of the second drum assembly.

Abstract: A snare strainer adapted to a snare drum is equipped with two strainers, which are attached to the opposite positions on the circumferential exterior of a cylinder of the snare drum and which control a snappy member to be selectively brought into contact with or separated from the backside head opposite to the drumhead. Herein, a moving base vertically moves along a fixed base attached to the circumferential exterior of the cylinder; holding members, which are tightly joined together so as to hold the terminal of the snappy member, are supported by a support member fixed to the moving base. The holding members are engaged with the support member due to a magnetic attraction exerted by permanent magnets. This makes it possible for the person to detachably attach the holding members to the support member without using tools; hence, it is possible to improve the handling of the snare strainer.

Abstract: Intended is to provide a strainer having a switch mechanism, which is hardly rattled by a wear, which can be stably operated by a weak force, which does not load a snare assembly and which can maintain an excellent operation feel, and a snare assembly holding structure which has a reliable clamping force so that it can prevent the looseness of the snare assembly end portion. An operation lever is hinged on its base end side to a base body. A link is turnably connected on its one end side to the lower side portion of a snare assembly holding member, and is likewise turnably connected on its other end side to a midway position of the operation lever. When the operation lever turns upward, the snare assembly holding member is pulled upward through the link. When the operation lever turns downward, the snare assembly holding member is pushed downward.

Abstract: The invention relates to a snare tension device for tensioning and releasing a snare wire. In the snare tension device a rotation movement of a rotation element is transferred to a pushing element by means of a transfer element.

Abstract: A strainer includes a strainer bodpy, a slider to which a cam follower is fixed, a holder to which snare wires are fixed, an operating lever, and a cam that is pivoted through operation of the operating lever. The slider is slid relative to the strainer body by pivoting the cam through operation of the operating lever so that the cam follower moves along the cam surface. The movement distance of the slider linearly changes with respect to an operation angle of the operating lever.