Slide operation apparatus

A slide operation apparatus capable of preventing a movable unit from being unintentionally moved in a box body, while being easy to assemble and simple in construction. The movable unit includes a gondola to which an operating element is fixed. The gondola is adapted to be movable relative to upper and lower guide bars. A sliding contact assembly includes a plate spring to which an insulation sheet is assembled. The sliding contact assembly in a curved state is mounted to a fixture portion of the operating element by having pawls of the plate spring engaged with notches formed in the fixture portion. During the entire movement process of the movable unit, the curved convex portion of the sliding contact assembly is in sliding contact with the lower guide bar.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a slide operation apparatus having a box body thereof in which a movable unit is disposed for movement when an operating element thereof is operated or manipulated, the slide operation apparatus being used for setting the volume or other parameter in a system mounted with the slide operation apparatus.

2. Description of the Related Art

Conventionally, there has been known a slide operation apparatus such as a fader mounted on a mixer or other system. The slide operation apparatus generally includes a box body in which a movable unit is disposed for movement. The movable unit can be moved, for example, by a user by grasping and manually operating an operating element fixed to the movable unit. The mixer or the like mounted with the slide operation apparatus detects the moving position of the movable unit, and sets the volume or other parameter based on the detected position.

Generally, the movable unit is adapted for movement in the box body longitudinally thereof by being guided by a round bar or other movement guide which is disposed in and longitudinally of the box body.

Also known is a slide operation apparatus capable of adjusting a sliding resistance between the movable unit and the movement guide during movement of the movable unit (Japanese Laid-open Patent Publication No. 2002-8907). This slide operation apparatus includes a squared U-shaped spring disposed to sandwich the movement guide with a sandwiching force appropriately settable by a screw, whereby the sliding resistance (sliding frictional force) can be adjusted.

As described above, however, the slide operation apparatus disclosed in Japanese Laid-open Patent Publication No. 2002-8907 requires the provision of the U-shaped spring and the screw for friction generation, resulting in a complicated construction of the friction generating mechanism, which poses a problem. Another problem is that the friction generating mechanism is not easy to assemble because the U-shaped spring must be mounted such as to sandwich the movement guide, and the screw must be attached.

In recent years, a slide operation apparatus has been known that does not include a brush-type detection device but includes a magnetic detection device or other non-contact detection device for position detection of the movable unit (Japanese Laid-open Patent Publication No. 2006-49302). This type of slide operation apparatus cannot utilize the sliding resistance between the movable unit and the position detection brush for the holding of the movable unit. As a result, the movable unit is freely movable and hence there is a fear that the movable unit is unintentionally moved such as being fallen from its original location depending on the mounting angle of the movable unit relative to the apparatus. To obviate this, the above described friction generating mechanism or other mechanism must be additionally provided to thereby apply an appropriate sliding resistance to the movable unit during the movement thereof.

The movable unit of the slide operation apparatus disclosed in Japanese Laid-open Patent Publication No. 2006-49302 includes a position sensor adapted to output a signal representing the position of the movable unit. A flexible flat cable for transmission of the detected signal is extended from the movable unit to the outside of the apparatus via a guide through hole formed in a housing of the apparatus. This type of slide operation apparatus includes a ground line through which is discharged a high voltage, if any, applied from the operating element operated by a user charged with static electricity.

Recently, a mixer or other signal processing system mounted with a plurality of slide operation apparatuses has been demanded to have a “touch sense function” to permit the mixer or other system to recognize which one of the slide operation apparatuses is currently operated. With the touch sense function, a channel in the mixer corresponding to one of the slide operation apparatuses which is currently operated or manipulated by a user is made active, or the data rewriting is enabled upon operation of the apparatus, for example. To realize the touch sense function, a ham noise detection line, for example, is provided in each of the slide operation apparatuses. The ham noise detection line is at the same electrical potential as the operating element of the slide operation apparatus, and is ungrounded. Upon detection of ham noise generated in the ham noise detection line when the user touches the operating element of any of the slide operation apparatuses, the touching to the currently operated operating element is detected.

On the other hand, however, the operating elements cannot electrically be grounded in order to achieve the touch sense function. In that case, when the user charged with high-voltage static electricity touches any of the operating elements, the slide operation apparatus can erroneously operate or become faulty, which poses a problem.

SUMMARY OF THE INVENTION

The present invention provides a slide operation apparatus capable of preventing a movable unit from being unintentionally moved in a box body, while being easy to assemble and simple in construction.

The present invention provides a slide operation apparatus capable of realizing a touch sense function to recognize a currently operated operating element, while ensuring the provision of a discharge path through which static electricity applied to the operating element can be discharged.

According to a first aspect of this invention, there is provided a slide operation apparatus comprising a box body having a slid portion, a movable unit having engaging portions and held in the box body to be movable longitudinally of the box body, an operating element fixedly mounted to the movable unit and adapted to be operated, and a plate spring having opposite ends thereof formed with engaged portions to correspond to the engaging portions of the movable unit, wherein the plate spring is adapted to be maintained in a curved state by having the engaged portions thereof engaged with the engaging portions of the movable unit, the plate spring having a curved convex portion thereof adapted to be in substantial sliding contact with the slid portion of the box body during movement of the movable unit.

The slide operation apparatus according to the first aspect of this invention can prevent the movable unit from being unintentionally moved in the box body, while being easy to assemble and simple in construction.

In the present invention, the slide operation apparatus can include an elongated movement guide provided as the slid portion in and longitudinally of the box body, the movable unit can be supported for sliding movement by the movement guide, and the curved convex portion of the plate spring can be adapted to be in substantial sliding contact with the movement guide during movement of the movable unit.

In that case, the movement guide has both a guide function and a sliding contact function, making it possible for the slide operation apparatus to have a much simpler and compact construction.

An insulation member can be assembled to the plate spring.

The curved convex portion of the plate spring can be adapted to be in sliding contact via the insulation member with the slid portion of the box body.

The slide operation apparatus can include an elongated movement guide provided as the slid portion in and longitudinally of the box body, and the insulation member can have a longitudinally center portion thereof formed with a through hole and disposed at the curved convex portion of the plate spring in contact with the movement guide, and friction can be generated by the contact between the longitudinally center portion of the insulation member and the movement guide, whereby the movable unit can be prevented from being unintentionally moved.

According to a second aspect of this invention, there is provided a slide operation apparatus comprising a box body made of an electrically conductive material and adapted to be grounded, a movable unit held in the box body to be movable longitudinally of the box body, an operating element including an electrically conductive knob and fixedly mounted to the movable unit, the operating element being adapted, when operated, to move the movable unit, a box body-side conductive part fixed relative to the box body and electrically conductive to the box body, a movable unit-side conductive part provided in the movable unit, the movable unit-side conductive part being ungrounded and electrically conductive to the electrically conductive knob of the operating element, and an insulation member provided in one of the box body-side and movable unit-side conductive parts and made in substantial sliding contact with another thereof to maintain a constant close distance between the box body-side and movable unit-side conductive parts during movement of the movable unit.

With the slide operation apparatus according to the second aspect of this invention, a touch sense function to recognize which one of operating elements is currently operated can be realized, while ensuring the provision of a discharge path through which static electricity applied to the operating element can be discharged.

The movable unit-side conductive part can be comprised of a plate spring, and the box body-side conductive part can be comprised of an elongated movement guide adapted to hold the movable unit for movement.

The insulation member can be formed with a through hole to which the movable unit-side conductive part is fitted.

Further features of the present invention will become apparent from the following description of an exemplary embodiment with reference to the attached drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention will now be described in detail below with reference to the drawings showing a preferred embodiment thereof.

FIG. 1shows in perspective view a slide operation apparatus according to one embodiment of this invention. The slide operation apparatus includes a box body, which is a housing of the apparatus and comprised of a main case10and a sub case40adapted to be assembled together.FIG. 2shows in perspective view the slide operation apparatus, with the sub case40detached therefrom.FIG. 3shows in plan view the slide operation apparatus.

As shown inFIG. 2, a movable unit70and upper and lower guide bars78,79which are round bars are disposed within the main case10of the slide operation apparatus. An elongated member50formed into a squared U-shape in section is provided in an upper portion of the main case10, and a motor59is disposed on one longitudinal end side of the elongated member50.

Generally, a plurality of slide operation apparatuses are mounted as fader apparatuses in desired orientations to a mixer or other system. For convenience of explanation, vertical and lateral directions referred to hereinbelow are determined as seen from the sub case40, with a knob81of an operating element80disposed on the upper side of the apparatus. Specifically, the direction toward the knob81is referred to as the “up direction”, the direction toward a motor59(seeFIG. 2) is referred to as the “left direction”, and the direction toward the reader viewingFIG. 2is referred to as the “front direction”.

As shown inFIG. 2, the main case10is comprised of a bottom plate11, a main plate12disposed on the rear side of the apparatus, a left-side plate13, a right-side plate14, and a top plate15. The top plate15has right and left end portions thereof extending forward to form mounting pieces16adapted to be mounted with the elongated member50. The main case10is integrally formed by an electrically conductive metal sheet such as a steel plate.

Support holes20,21for holding the upper guide bar78are formed on the upper side of the left- and right-side plates13,14of the main case10, and support holes22,23for holding the lower guide bar79are formed on the lower side thereof. As shown inFIG. 1, a cable insertion hole24is formed in a longitudinally center portion of the main plate12of the main case10.

As shown inFIG. 2, the elongated member50is fixed via the mounting pieces16to the main case10by screws25,26. As shown inFIGS. 2 and 3, a slit55along which the operating element80is moved is longitudinally formed in a bottom portion of the elongated member50. Mounting pieces51,52are provided in upper left and right end portions of the elongated member50. The assembled slide operation apparatus is mounted to a mixer or the like (not shown) by having the mounting pieces51,52fixed by screws53,54to a panel plate of the mixer or the like.

As shown inFIG. 3, a pulley56is attached to an output shaft (not shown) of the motor59to project from a left end portion of the elongated member50, and a belt rest pin58is provided in a right end portion of the elongated member50to project therefrom. A rubber belt57is extended between the pulley56and the belt rest pin58. A belt fixture85is fixed to the operating element80, and the rubber belt57is fixed at its intermediate portion to the belt fixture85. When the rubber belt57is reciprocated with forward and reverse rotation of the motor59, the knob81of the operating element80and the movable unit70formed integrally with the operating element80are reciprocated in the longitudinal direction of the elongated member50. For example, upon scene recall operation being performed, a driving current is supplied to the motor59, whereby the movable unit70is automatically driven by the motor59to a desired position. Alternatively, the user can move the movable unit70to a desired position by manually operating or manipulating the knob81of the operating element80. The knob81is made of an electrically conductive material as described later, and covered by a grasped portion34made of rubber or the like (seeFIG. 2). Upon manual operation, the user can grasp the grasped portion34of the knob81.

The sub case40(seeFIG. 1) is integrally formed by a resin into a squared U-shape as viewed in plan. The sub case40is assembled to the main case10by having engagement portions, not shown, of these cases engaged by snap fitting with one another. As shown inFIG. 1, the left plate41of the sub case40is formed with notches42,43to respectively correspond to the upper and lower guide bars78,79. Although not shown, the sub case40has its right plate constructed similarly to and symmetrically with the left plate41.

As shown inFIG. 2, a circuit board72is mounted to the movable unit70. For example, the circuit board72is attached by screws or the like to a front surface of a rear portion71aof the gondola71of the movable unit70(seeFIG. 4B). A magnetic sensor73comprised of, for example, an IC including a hall element is disposed on a front surface of the circuit board72.

Furthermore, a flat cable30is attached to the circuit board72. The flat cable30, which is disposed in the main case10, includes a cable proximal portion31thereof fixed to the circuit board72and an extended portion32thereof extending from the cable proximal portion31. The extended portion32is extended rightward from the cable proximal portion via a cable run-off portion96aof a right wall96of the gondola71, and is then folded back leftward to extend to the outside via a cable insertion hole24(seeFIG. 1). The folded-back position of the extended portion32changes depending on the moving position of the movable unit70in the left-to-right direction to follow the movement of the movable unit70.

FIG. 4Aschematically shows the movable unit70as seen from front.FIG. 4Bis a section view taken along line A-A inFIG. 4A. InFIG. 4A, an illustration of the circuit board72and the sensor73is omitted.

As shown inFIGS. 4A and 4B, the movable unit70includes the gondola71made of resin and formed into a rectangular box shape having an open front side, and the operating element80is fixed to the gondola71. The operating element80includes the knob81formed into a T-shape as seen from front, and includes a fixture portion82disposed below the knob81and having a rectangular outer shape as seen from front. The operating element80is integrally formed by an electrically conductive material. The fixture portion82is fixed to the gondola71by being outsert-molded or bonded thereto, for example.

The gondola71has its left and right walls95,96each formed with one upper through hole and one lower through hole extending therethrough in the left-to-right direction. The upper guide bar78extends through the upper through holes, and the lower guide bar79extends through the lower through holes, whereby the gondola71can slidably be moved relative to the upper and lower guide bars78,79. Thus, the movement of the gondola71is guided by the guide bars78,79.

A mechanism for detecting the position of the movable unit70is provided, which is similar to a known mechanism disclosed in Japanese Laid-open Patent Publication No. 2006-49302. Specifically, as shown inFIG. 2, the upper guide bar78is formed at its lower surface with a magnetic pole surface88over substantially the entire longitudinal length thereof. The magnetic pole surface88is magnetized alternately with N and S magnetic poles. The upper guide bar78is formed into a circular shape in section with a flat lower surface. Thus, a lower surface of the magnetic pole surface88, corresponding to the lower surface of the upper guide bar78, is formed into a flat surface. The position of the gondola71in the upward-to-downward and forward-to-rearward directions is restricted by the upper guide bar78. Thus, a movement locus of the gondola71is restricted by the upper guide bar78, whereby a stable movement of the movable unit70is ensured and the accuracy of position detection of the movable unit70is enhanced.

Although not shown, a whirl-stop mechanism for the upper guide bar78is provided at an appropriate portion of the box body, which is a housing of the slide operation apparatus, whereby the magnetic pole surface88of the upper guide bar78can always be directed downward. The whirl-stop mechanism can be realized, for example, by forming the above described through hole, not shown, of the gondola71through which the upper guide bar78extends or the support holes20,21of the main case10to have a sectional shape similar to that of the upper guide bar78, which is circular in section with the flat lower surface. The sensor73(seeFIG. 2) is disposed beneath the upper guide bar78to face the magnetic pole surface88of the upper guide bar78, with a slight gap (clearance) between the sensor73and the magnetic pole surface88.

With movement of the movable unit70, the sensor73is moved relative to the magnetic pole surface88of the upper guide bar78and outputs a pulse signal each time the sensor73passes through a boundary between N and S poles of the magnetic pole surface88. Based on the number of pulse signals, an amount of movement of the movable unit70can be detected. The magnetic poles formed on the magnetic pole surface88are arranged, for example, in two rows. The magnetic poles disposed in one of the rows are shifted by π/2 in terms of phase relative to those disposed in another row in the longitudinal direction of the upper guide bar78, and two series of pulse signals which are shifted in phase are output from the sensor73. Thus, the moving direction (right or left) of the movable unit70can be detected based on the direction of the phase shift in pulse signals. The current position of the movable unit70is detected based on the detected amount and direction of movement and position information indicating a position before movement and stored in a control circuit of the mixer, not shown. Needless to say, the movement of the movable unit70can be detected by the sensor73even when the movable unit is manually moved.

As shown inFIG. 2, the upper and lower guide bars78,79with which the gondola71is engaged are supported by having opposite end portions thereof inserted through support holes20to23of the main case10. The upper guide bar78is disposed such that the magnetic pole surface88is directed downward.

As shown inFIGS. 4A and 4B, a hole71bis formed in a rear portion71aof the gondola71, and a hole83corresponding to the hole71bis formed in the fixture portion82of the operating element80. A pair of left and right notches83a(engaged portions) are formed in the fixture portion82of the operating element80in communication with the hole83at a vertical position where the lower guide bar79is disposed. Run-off portions71ba(engaging portions) corresponding to the notches83aare formed in the rear portion71aof the gondola71in communication with the hole71b. A sliding contact assembly60is interposed between the lower guide bar79and the fixture portion82of the operating element80. The sliding contact assembly60is engaged with and mounted to the fixture portion82.

FIGS. 5A and 5Brespectively show in front view a plate spring61and an insulation sheet64of the sliding contact assembly60.FIGS. 5C and 5Dschematically show how the sliding contact assembly60is assembled and is engaged with and mounted to the fixture portion82of the operating element80.

The sliding contact assembly60is comprised of the plate spring61and the insulation sheet64which are assembled together. The plate spring61is made of an electrically conductive metal, and includes a barrel portion62thereof formed at its longitudinal opposite ends with pawls63. The plate spring61per se has a peculiar of being curved (being convex upward in the example shown inFIG. 5C) in a free state, and has such a characteristic that an inversely curved state can be attained by being pressed at its convex side and can be stably maintained thereafter. It should be noted that the plate spring61may be flat in a free state.

The insulation sheet64is integrally formed by an insulating material such as resin. As shown inFIG. 5B, the insulation sheet64has its longitudinally opposite end portions formed with a pair of engagement holes66corresponding to the pawls63of the plate spring61, and has its longitudinally center portion formed with a through hole65for electric discharge. To assemble the sliding contact assembly60, as shown inFIG. 5C, a concave side of the plate spring61is made to face the insulation sheet64, and in this state, the pawls63of the plate spring61are inserted into the engagement holes66of the insulation sheet64. Then, a convex side of the plate spring61is pressed to reverse the direction of curvature of the plate spring61, whereby the new convex side of the plate spring61is made in close contact with the insulation sheet64. As a result, the insulation sheet64and the plate spring61are made integral together.

FIGS. 5E and 5Fshow in enlarged scale an A portion and a B portion inFIG. 5C, respectively. The assembled sliding contact assembly60is mounted to the gondola71before the upper and lower guide bars78,79are inserted into the gondola71. Specifically, as shown inFIGS. 4B and 5D, the pawls63of the plate spring61, which project from the engagement holes66of the insulation sheet64, are inserted for engagement into notches83a, which are in communication with the holes83of the fixture portion82of the operating element80, whereby the sliding contact assembly60in a curved state is mounted to the fixture portion82. Subsequently, the upper and lower guide bars78,79are inserted into the gondola71.

The sliding contact assembly60mounted to the fixture portion82is curved to an extent that it is in contact with the lower guide bar79. Specifically, a longitudinally center part (where the through hole65is formed) of the insulation sheet64is a convex portion of the sliding contact assembly60and in contact with the lower guide bar79(seeFIG. 5E). The contact between the insulation sheet64and the lower guide bar79is maintained even during movement of the movable unit70. Thus, during the entire movement process of the movable unit70, the sliding contact assembly60is in sliding contact with the lower guide bar79. As a result, a desired friction is generated, whereby the movable unit70is prevented from being unintentionally moved. Due to the interposition of the insulation sheet64between the plate spring61and the lower guide bar79, the plate spring61per se is kept out of contact with the lower guide bar79during the entire movement process of the movable unit70. However, the plate spring61is disposed close to the lower guide bar79with a constant distance corresponding to the thickness of the insulation sheet64(equal to or less than about 100 μm) The plate spring61and the lower guide bar79are disposed close to each other especially at the through hole65, without any element interposed therebetween.

A friction force produced between the sliding contact assembly60and the lower guide bar79is determined depending on the degree of curvature and length of the sliding contact assembly60, the spring constant of the plate spring61, and so on. For example, the friction force is set to have a magnitude that permits the movable unit70to be retained at its original location without being fallen therefrom, even when the slide operation apparatus is mounted to the mixer with the lower guide bar79vertically disposed.

FIG. 6Aschematically shows electrical wiring connections around the operating element80and the circuit board72. InFIG. 6A, the grasped portion34of the operating element80is shown in section. As described above, the knob81is covered by the grasped portion34made of rubber or the like (seeFIG. 2). As shown inFIG. 6A, the grasped portion34is fitted and fixed to the knob81. An electrically conductive plating28is continuously formed not only on an outer surface of the grasped portion34which is directly grasped for operation by a user but also on an inner surface thereof which is in contact with the knob81. Thus, the surfaces of the grasped portion34are electrically conductive to the fixture portion82of the operating element80via the knob81.

In the slide operation apparatus, there are provided a power supply line92, three signal lines93(93-1to93-3) for transmission of signals output from the sensor73, and a ham noise detection line94. These lines92to94are contained in the flat cable30shown inFIG. 2, and disposed parallel to the longitudinal direction of the extended portion32of the cable30.

In the circuit board72, the power supply line92and the three signal lines93are connected to the sensor73. When the slide operation apparatus is in use, a voltage of +5 V is applied to the power supply line92. Pulse signals output from the sensor73are drawn via the signal lines93, whereby the current position of the movable unit70is detected. The ham noise detection line94is electrically connected via a connection line, not shown, to the fixture portion82, whereby the line94and the fixture portion82are always at the same potential.

In an electrical path formed by the electrically conductive plating28, the knob81, the fixture portion82, the sliding contact assembly60, the lower guide bar79, and the main case10, there is an electrically insulative part, which extends over a distance corresponding to the thickness of the insulation sheet64, only between the plate spring61of the sliding contact assembly60and the lower guide bar79, as described above. That part of the electrical path extending from the electrically conductive plating28of the operating element80to the plate spring61is in an electrically conductive state and is ungrounded. On the other hand, the main case10is electrically grounded via the mixer on which if the slide operation apparatus is mounted. The lower guide bar79is also grounded since the lower guide bar79is always in contact with the main case10.

FIG. 6Bshows in block diagram a touch detection circuit in the circuit board72that realizes a touch sense function. A plurality of the slide operation apparatuses which are similar in construction can be mounted to the mixer (not shown). The touch sense function is a function to cause the mixer to recognize which one of the slide operation apparatuses is currently operated. Based on the touch sense function, when the grasped portion34of the operating element80of any of the slide operation apparatuses is grasped for operation by a user, a channel in the mixer corresponding to the currently operated apparatus is made active, or a data rewriting operation is performed in the mixer upon the apparatus being operated, for example. In the mixer, it is determined that there is a touch state when the user touches the grasped portion34of the operating element80of any of the apparatuses, whereas there is a non-touch state when the user takes his/her fingers off the grasped portion34thereof.

A touch detection circuit37is provided in each of the slide operation apparatuses, and a CPU99is provided in the mixer. The touch detection circuit37includes an OSC (oscillator)38that generates a sinusoidal wave signal, and various circuits39including a full-wave rectifier, a differential amplifier, an A/D converter, etc., which are not shown individually.

As shown inFIG. 6A, the operating element80(more specifically, the grasped portion34thereof) of each of the slide operation apparatuses is connected with high impedance to the lower guide bar79. Thus, the ham noise detection line94, which is at the same potential as the electrically conductive plating28of the grasped portion34, is liable to pick up ham noise generated when the user touches the grasped portion34of the operating element80of the slide operation apparatus. By detecting the ham noise, the touching to the operating element80of the slide operation apparatus is detected.

Specifically, when the user touches the operating element80(more specifically, the grasped portion34thereof), there is produced a change in the electrostatic capacitance of a system, including the user's body to the ham noise detection line94, due to the presence of resistance and capacitance of the user's body, thereby changing the amplitude level of output of an LPF (low pass filter), not shown, in the OSC38(seeFIG. 6B). The change in amplitude is detected by the various circuits39from which a change signal is output to the CPU99of the mixer. Based on the change signal, the CPU99can recognize the touch/non-touch state of each of the slide operation apparatuses mounted on the mixer.

With the above described arrangement, when the user charged with static electricity operates or manipulates the operating element80, a high voltage is instantaneously applied to the plate spring61via the electrically conductive plating28of the grasped portion34, the knob81, and the fixture portion82of the operating element80. If an excessively high voltage (for example, equal to or higher than 5 kV) is applied to the plate spring61, a spark is generated in the through hole65between the plate spring61and the lower guide bar79, and is discharged via the lower guide bar79and the main case10.

According to the present embodiment, during the entire movement process of the movable unit70, the curved convex portion of the plate spring61of the sliding contact assembly60is in sliding contact with the lower guide bar79. Due to the friction between the convex portion of the plate spring61and the lower guide bar79, the movable unit70is prevented from being unintentionally moved within the box body of the apparatus no matter what posture the slide operation apparatus takes. Furthermore, the sliding contact assembly60comprised of the plate spring61and the insulation sheet64(seeFIG. 5C) is mounted to the fixture portion82of the operating element80by having the pawls63of the plate spring61engaged with the notches83aformed in the fixture portion82(seeFIGS. 4B and 5D). Thus, it is unnecessary to fix the assembly60to the operating element80by screws or the like, making it possible to simplify construction, reduce costs, and achieve ease of assembly.

In particular, the sensor73which is of a non-contact type does not produce physical resistance to the movement of the movable unit70, and is thus suitable for use with a friction generating mechanism comprised of the sliding contact assembly60. It should be noted that the sensor73can be of any type other than a non-contact type including a magnetic or optical sensor.

A combination of the sliding contact assembly60and the lower guide bar79achieves both the movement guiding function for the movable unit70and the braking function based on sliding contact, thereby preventing the construction from being complicated and easily making the apparatus compact.

Moreover, according to the present embodiment, the plate spring61of the sliding contact assembly60is always out of contact with the lower guide bar79during the entire movement process of the movable unit70, making it possible to realize a touch sense function. In addition, during the entire movement process of the movable unit70, the insulation sheet64of the sliding contact assembly60is in sliding contact with the lower guide bar79so that the plate spring61is always disposed close to the lower guide bar79with a constant distance corresponding to the thickness of the insulation sheet64. As a result, a discharge path through which static electricity applied to the operating element80can be discharged is always ensured by the through hole65formed in the insulation sheet64, making it possible not only to realize the touch sense function but also to reduce a fear of erroneous action and faulty of the apparatus caused by a high voltage generated when a user charged with high-voltage static electricity touches the operating element80of the apparatus.

Various modifications can be made as described below with reference toFIGS. 7A to 9D.

FIGS. 7A to 7Dshow an operating element80and a sliding contact assembly60according to a first modification.FIG. 7Ashows in fragmentary front view the fixture portion82of the operating element80, andFIGS. 7B to 7Drespectively show in front view plate springs61A to61C which are different in length from one another. As shown inFIGS. 7B to 7D, there are prepared a plurality of types (for example, three types) of plate springs61A to61C which are different in length from one another. As shown inFIG. 7A, the fixture portion82of the operating element80is formed with two pairs of engagement holes86A,86B. Then, a desired one of the plate springs61A to61C is selected as the plate spring61to be attached to the fixture portion82of the operating element80, and pawls63of the selected plate spring61are engaged with either the pair of engagement holes86A or another pair of engagement holes86B, whereby the degree of curvature of the plate spring61, i.e., the intensity of contact between the assembly60and the lower guide bar79can be adjusted, making it possible to adjust the resultant friction force. In this modification, a six-stage adjustment can be performed by selecting the plate spring61from among the three types of plate springs61A to61C and selecting one pair of engagement holes86from among the two pairs of engagement holes86A,86B. The number of types of plate springs and the number of pairs of engagement holes are not limitative thereto. More than three types of plate springs can be prepared and more than two pairs of engagement holes can be formed in the fixture portion82of the operating element80.

In the above described embodiment, the insulation sheet64of the sliding contact assembly60functions to maintain a constant close distance between the plate spring61and the lower guide bar79. Only from the viewpoint of ensuring the provision of the discharge path, however, the electrically conductive part to be kept apart at a constant distance from the lower guide bar79is not limitative to the plate spring61, but may be any electrically conductive part which is at the same potential as the conductive plating28of the operating element80(seeFIG. 6A) and disposed on the side of the movable unit70.

FIG. 7Eshows in fragmentary enlarged section view a sliding contact assembly according to a second modification. As shown inFIG. 7E, the sliding contact assembly includes a curved elastic insulation member164corresponding to the insulation sheet64and the plate spring61of the assembly60of the above described embodiment. The insulation member164is disposed in contact with the lower guide bar79, and formed with a hole165into which an electrically conductive member67of the sliding contact assembly is fixedly fitted, with a constant distance provided between a tip end67aof the electrically conductive member67and the lower guide bar79. Although not shown, the electrically conductive member67is at the same potential as the electrically conductive plating28via the fixture portion82of the operating element80. The insulation member164may be one not having a spring property. In that case, a sheet similar to the insulation sheet64is used in combination with a plate spring. The plate spring cannot be used to constitute a discharge path but can be used to maintain the sheet in a curved state.

Also with the arrangement according to the second modification, a discharge path for high-voltage static electricity applied to the operating element80is formed between the tip end67aof the electrically conductive member67and the lower guide bar79in the hole165formed in the insulation member164of the sliding contact assembly, whereby the effect of ensuring the provision of the discharge path, which is similar to that attained by the above described embodiment, can also be achieved in the second modification.

In the above described embodiment, the sliding contact assembly60is comprised of the insulation sheet64and the plate spring61which are assembled together, but this is not limitative.FIG. 7Fshows in front view a third modification of the sliding contact assembly. In this sliding contact assembly160, an insulation coating68is applied to a surface of the plate spring61on the side facing the lower guide bar79. The insulation coating68is formed with a non-coating portion68a, which corresponds to the through hole65(seeFIG. 5B), for ensuring the provision of a discharge path.

In the above described embodiment, the sliding contact assembly60is adapted to be in sliding contact with the lower guide bar79. However, in a case where the movable unit70is not required to have both the movement guide function and the sliding contact-based braking function, the sliding contact assembly60can be made in sliding contact with any part of the apparatus that is fixedly disposed relative to the main case10and electrically conductive to the main case10, as exemplarily shown inFIG. 8AtoFIG. 8D.

FIGS. 8A and 8Bschematically show in side and plan views a modification of the sliding contact assembly60. As shown inFIGS. 8A and 8B, the sliding contact assembly60is mounted to the fixture portion82of the operating element80, with its curved convex side directed rearward, i.e., toward the main plate12of the main case10. During the entire movement process of the movable unit70, the convex portion of the sliding contact assembly60is in sliding contact with the main plate12.

FIGS. 8C and 8Dschematically show in side view and front view another modification of the sliding contact assembly60. As shown inFIGS. 8C and 8D, the fixture portion82of the operating element80has a lower part thereof having an extended portion82awhich is extended forward. The sliding contact assembly60is mounted to the extended portion82aof the fixture portion82, with its curved convex side directed downward, i.e., toward the bottom plate11of the main case10. During the entire movement process of the movable unit70, the convex portion of the sliding contact assembly60is in sliding contact with the bottom plate11.

In the above described embodiment, the insulation sheet64, as an insulating part to achieve an insulating function in an electrical path extending from the operating element80to the main case10, is disposed on the movable unit70side, i.e., on the moving side of the apparatus. However, as exemplarily shown inFIGS. 9A to 9D, the insulating part can be provided on the stationary side of the apparatus such as the main case10, or on both the moving and stationary sides of the apparatus.

FIGS. 9A to 9Cschematically show in perspective view, plan view, and front view a modification of the insulating part. As shown inFIGS. 9A to 9C, insulating parts97(97A and97B) extending in the left-to-right direction are fixed onto a front surface of the main plate12of the main case10. A slit98providing a discharge path like the through hole65(seeFIG. 5B) is formed between the insulating parts97A,97B. Each insulating part97has a thickness nearly the same as that of the insulation sheet64(seeFIG. 5B).

A sliding plate spring260equivalent to the sliding contact assembly60of the embodiment is only comprised of a plate spring, without having the insulation sheet64assembled thereto. The sliding plate spring260is mounted to the fixture portion82of the operating element80, with its curved convex side directed rearward, i.e., toward the main plate12of the main case10. During the entire movement process of the movable unit70, the convex portion of the sliding plate spring260is in sliding contact with both the insulating parts97A,97B and maintained at a distance, corresponding to the thickness of the insulating parts97, from the main plate12.

With the above described arrangement, a discharge path for high-voltage static electricity applied to the operating element80is formed by the slit98between the sliding plate spring260and the main plate12, whereby the effect of ensuring the provision of discharge path, similar to that attained by the above described embodiment, can be achieved.

The insulating parts can be provided on both the moving and stationary sides of the apparatus, as shown inFIG. 9Din which another modification of insulating parts is shown. Specifically, on the stationary side of the apparatus, the insulating parts97A,97B are provided in the main plate12of the main case10, as in the case shown inFIGS. 9A to 9C. On the moving side of the apparatus, there is provided the sliding contact assembly60(see FIG.5C) comprised of the plate spring61and the insulation sheet64. In that case, a discharge path is formed by the slit98between the insulating parts97A,97band the through hole65formed in the insulation sheet64. In that case, it is preferable that the distance between the main plate12and the plate spring61, which is equal to the total thickness of the insulating parts97and the insulation sheet64, should be set appropriately by making the total thickness equal to or less than about 100 μm.

In the above described embodiment and modifications, the pawls63are formed in the plate spring61, and the notches83aand the engagement holes86are formed in the fixture portion82of the operating element80, thereby permitting the sliding contact assembly60,160, or260to be mounted to the fixture portion82of the operating element80. However, this is not limitative so long as the sliding contact assembly60or the like can be maintained in a curved state. For example, instead of the notches83aand the engagement holes86, recesses or the like can be formed. The plate spring61can be formed with notches or engagement holes, and the fixture portion82can be formed with pawls. Two or more pawls or other engaged portions can be provided in each of left and right sides of one of the plate spring61and the fixture portion82, and a corresponding number of notches or engagement holes or other engaging portions can be formed in another of the plate spring61and the fixture portion82.

In a case where the touch sense function is not required, countermeasure for static electricity noise can easily be provided by maintaining the operating element80and the main case10at the same potential by, for example, removing the insulation sheet64from the sliding contact assembly60.