JP4081632B2 - Pressure sensor for touch control of electronic keyboard instruments - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pressure sensor for touch control used in a keyboard device of an electronic musical instrument such as an electronic piano or an electric tone.
[0002]
[Prior art]
Electronic musical instruments with touch control function can change the strength of the sound at the start of the sound or in the continuous state by changing the force applied to the key when the key is pressed or the key is pressed, vibrato effect, tremolo effect Etc. are generated or changed. For this purpose, the keyboard device is provided with a pressure sensor for touch control (also referred to as a pressure control sensor) that senses the key pressing pressure. The operating range of the key is appropriately restricted by contacting the buffer member after the key itself or its interlocking member performs a certain operation. The pressure sensor is provided on the front surface or back surface of the buffer member (stopper member) that receives the key pressing pressure during or after the key full stroke for the purpose of controlling sound generation according to the key pressing stroke or the subsequent key pressing pressure. It is often done. FIG. 4 shows an example of the arrangement of the buffer members in the keyboard device. In this example, when the key K is depressed, the projection k1 provided at the front part (performer side) of the key pushes down the lever L, the rear part of the lever L rises, and comes into contact with the buffer member A.
[0003]
As shown in FIG. 27, both pressure sensors extend in a band shape over a range corresponding to all keys or a range corresponding to a key to which a touch control function is to be provided. Depending on the pressure sensor, the buffer member A is bonded to the sensor body S as shown in the figure.
[0004]
Among the buffer members, there are a single layer type having a single material buffer member as shown in FIG. 27 and a plurality of types of buffer members A1, A2, A3, A4 as shown in FIG. There are multi-layer types that are stacked in the direction of receiving key pressing pressure. The multi-layer type cushioning member is a combination of hard and soft materials that can be used to smoothly change the cushioning action from the beginning to the end of the contact between the moving part and the cushioning member when the key is pressed. The buffer members are also bonded to each other with an adhesive.
[0005]
However, any type of pressure sensor may cause the following problems because adhesion between the buffer member and the sensor main body or between the multiple layers of the buffer member is performed on the entire contact surface.
[0006]
In a pressure sensor provided with a single layer type buffer member, as shown in FIG. 29, dust a or oil b may be interposed between the buffer member and the sensor body, or air c may be included. In addition, since the bonding surface extends over the entire surface, inadequate position adjustment of the bonding surface accumulates in the length direction, and the bonding may be performed with wrinkles and twists d.
[0007]
In the pressure sensor provided with the multilayer buffer member, as shown in FIG. 30, dust a, oil b, air c, wrinkles and twists d are also present between the multilayer buffer members constituting the buffer member. In particular, a thick adhesive layer e may be present in the form of a plate or a lump.
[0008]
In this way, when dust, wrinkles, etc. are present on the bonding surface, there is a difference in shearing force generated by deformation through the bonding surface in the non-bonded portions (a, b, c) as shown in FIG. The key pressing pressure is not properly transmitted. When wrinkles are present, local distortion is fixed, which affects the sensitivity of the pressure sensor. Further, if there is a thick adhesive layer e, the portion has higher rigidity than the other portions, and a difference in transmission rate occurs, so that proper key pressing pressure cannot be transmitted. Due to such poor transmission of the key pressing pressure, the output of the pressure sensor is disturbed, and the control performance varies depending on the key, which hinders accurate touch control.
[0009]
[Problems to be solved by the invention]
The present invention provides a pressure sensor for touch control of an electronic keyboard instrument that can solve the above-mentioned problems of the prior art and can realize accurate touch control under a structure in which a pressing force is received via a buffer member. Objective.
[0010]
[Means for Solving the Problems]
The object of the present invention is to arrange a buffer member that abuts with a buffering action and delimits a key pressing stroke to an operation part that is a part of a key or a part of a member that is interlocked with the key when the key is pressed, and is disposed on the buffer member. A pressure sensor including a sensor body for touch control, wherein the partial contact is intermittently performed in the key arrangement direction on the contact surface between the buffer member and the sensor body, It is achieved by a pressure sensor for touch control of a keyboard device, characterized in that it is performed as adhesion at a position necessary for adhesive strength in an intermediate region of the contact position on the buffer member between the adjacent operation parts ( First invention).
[0011]
The above-mentioned object of the present invention also includes a buffer member that abuts with a buffering action on a part of the key or a part of the member that interlocks with the key when the key is pressed, and delimits the key pressing stroke, and overlaps the buffer member. A pressure sensor including a sensor body for touch control, wherein the buffer member is formed by stacking a plurality of buffer members in a layered manner, and a key arrangement direction is provided on at least one contact surface between the layers In this case, the partial bonding is performed as a bonding at a position necessary for the bonding strength in the intermediate region of the contact position of the adjacent operation part on the buffer member. This is achieved by a pressure sensor for touch control of a keyboard device characterized by the above (second invention).
[0012]
The object of the present invention is further to receive a pressing force via a buffer member from an operation part which is a part of a key or a part interlocked with the key when the key is pressed, and present a sensor output corresponding to the pressing force. A pressure sensor for touch control of an electronic keyboard instrument provided with a main body, wherein a gap is formed between the sensor main body and a pressing member located on one of both sides in the pressing direction when not pressed. And a gap forming member is provided (third invention).
[0013]
The gap forming member can be formed of a material that does not elastically deform when pressed to such an extent that the buffer member does not contact the sensor body unless the buffer member is elastically deformed.
[0014]
The gap forming member may include an elastic member arranged so as to be elastically deformed in a direction substantially perpendicular to the pressure-sensitive surface of the sensor body when pressed.
[0015]
The gap forming members are provided so as to extend in the key arrangement direction with a space between each other, and the gap between the gap forming members is narrow at a position corresponding to the center of the pressing position by the operating portion, and the center corresponding position. It can be assumed that it is gradually changing so as to become wider as it moves away from.
[0016]
The gap forming member may be a thin plate and have an opening at each position where the pressing force is applied by the operating portion.
[0017]
Furthermore, the gap forming members are provided so as to extend in the key arrangement direction with a space between each other, and the width of each gap forming member varies depending on the position in the thickness direction. The interval near the sensor body may be wider than the interval near the buffer member.
[0018]
The sensor body includes a sheet material having a pressure-sensitive function facing each other and a spacer interposed between the sheet materials, and the portion of the gap forming member closer to the sensor body is the spacer and the sheet material. It can be provided so that the positions overlap in the thickness direction.
[0019]
The gap forming member can be formed by a part of a case that houses the sensor body.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows an example of a pressure sensor according to the first aspect of the present invention. In the figure, the direction in which the buffer member is struck by the operation part which is a part of the key or a part of the member interlocked with the key when the key is pressed is shown from above. This direction is not restricted to what is shown in the figure. For example, as shown in FIG. 4, when the lever H hits the buffer member, the hit is from below. In the following description, members and parts of the same type in the drawings are given the same reference numerals and description thereof is omitted.
[0021]
The illustrated pressure sensor includes a sensor body 1 and a single-layer type buffer member 2. For example, as shown in a cross section in FIG. 2, the sensor main body 1 has two sensor sheets 10 using elastic plates such as rubber sheets, plastic films, and the like. Then, two flexible electrodes 12 can be fixed below the inner surface, and one flexible electrode 13 straddling the two electrodes can be fixed above. The flexible electrode has an appropriate resistance. As a result, the sensor body 10 is bent by the pressing force from above, and the upper and lower flexible electrodes come into contact with each other according to the amount of bending, and the resistance value between the electrodes decreases as the contact area increases. Let As a result, since the voltage between these electrodes changes, it is possible to perform touch control of musical sounds using the change.
[0022]
In addition, as the sensor body, various forms such as those exemplified below can be used.
(i) One of the opposing sensor constituent members is provided with two elongated electrodes spaced apart from each other and extending in the longitudinal direction on the opposing surface, and the other sensor constituent member is a pressure sensitive conductive rubber, barium titanate, or the like As described above, a pressure-sensitive member made of a material that changes conductivity according to pressure is provided on the opposite surface. This is because when the key pressing pressure is applied through the buffer member, one of the sensor constituent members is deformed and comes into contact with the electrode of the other sensor constituent member, and the conductivity of the conductive seating amount changes according to the key pressing pressure, As a result, the voltage between the electrodes changes.
(ii) A belt-like film is folded in two at a fold extending in the longitudinal direction, and pressure-sensitive conductive ink is printed on each of the overlapping opposing surfaces, and the edges of the two conductive ink layers on different sides A conductor extending in the longitudinal direction of the film along the portion and reaching the terminal at the end of the film. This is to obtain the sensor output corresponding to the pressing force by utilizing the fact that the conductive ink layer that has received the pressing force accompanying the key pressing decreases the resistance value and changes the voltage between the two conductors. .
(iii) A type in which two strip-shaped metal plates are separated by an insulating spacer and a voltage is applied between them to detect the capacitance between the metal plates. This is to obtain a sensor output corresponding to the pressing force by utilizing the fact that the metal plates that have received the pressing force accompanying the key pressing approach each other and change the capacitance.
(iv) Insulating plate and metal plate are spaced apart by a spacer, and a spiral coil is printed on the surface of the insulating plate to cause current to flow, generating eddy current in the metal plate. This type detects the current loss of the spiral coil caused by it. This is because the plates that have received the pressing force associated with the key pressing approach each other and increase the induced eddy current of the metal plate and the accompanying coil current loss, thereby obtaining a sensor output corresponding to the pressing force. Is.
(v) Thick pressure-sensitive rubber brought into contact with two elongated electrode surfaces that are spaced apart from each other and extend in parallel. This is because the pressure-sensitive rubber that receives the pressing force accompanying the key pressing reduces the resistance value and changes the voltage value between the two electrode surfaces, thereby obtaining a sensor output corresponding to the pressing force. It is.
[0023]
In this example, the buffer member 2 is constituted by a single buffer member. As the cushioning member, various elasticity and hardness felt materials generally used for acoustic pianos as red felt, green felt, white muffler felt, elasticity such as gel resin material made of foamed resin material, silicon, etc. A member can be used.
[0024]
The sensor body 1 and the buffer member 2 extend in a band shape over a range corresponding to all keys of the keyboard device or over a range corresponding to a key to which a touch control function is to be provided. These contact surfaces are adhered by an adhesive, and the form thereof is, for example, partial adhesion as follows.
[0025]
In the contact surface between the buffer member 2 and the sensor main body 1 shown in FIG. 1, the section N is an intermediate region between the contact positions of the adjacent operation parts on the buffer member, that is, positions where the adjacent operation parts contact the buffer member. An area corresponding to the intermediate position is shown. An area other than the intermediate section N indicates a sensing section P for sensing key pressing pressure by the sensor body 1. In the intermediate section N, adhesion is applied to a place necessary for adhesive strength, that is, a place necessary for fixing between the sensor body 1 and the buffer member 2. In this example, a bonding portion M having a necessary width is formed in two necessary sections N among the three sections N shown in the drawing.
[0026]
The position and width of the bonding portion M necessary for the bonding strength in the intermediate section N are determined according to physical and chemical properties such as the size, flexibility, and adhesiveness of the member. For example, the bonding location M may be formed in all the intermediate sections N in the drawing, or the entire width of the section N may be the bonding location M as required.
[0027]
The pressure sensor is fixed to the keyboard frame of the keyboard device by bonding, screwing, or an appropriate fixing member.
[0028]
Thus, the intermediate region of the contact position on the buffer member of the adjacent operation part is set as the intermediate zone N, the other region is set as the sensing zone P, and the portion necessary for the adhesive strength in the intermediate zone N is set as the bonding location. Thus, the following advantages can be obtained.
[0029]
Depending on the size, material, etc. of the buffer member 2, when the operating portion of the key or its interlocking portion exerts a key pressing pressure on the contact surface between the sensor body 1 and the buffer member 2, the width of the operating portion is slightly wider than that. Only the contact surface corresponding to the width receives the key pressing pressure, and the other portions do not receive the key pressing pressure. In this case, on the contact surface, an area where the key pressing pressure is not received from the operation part of each key is defined as an intermediate section N, and a position and a width necessary for fixing the sensor body 1 and the buffer member 2 are defined in the section N. By selecting and setting the bonding location M, the key pressing pressure applied to the buffer member 2 acts on the sensor body 1 via the sensing section P in the contact surface without passing through the adhesive layer.
[0030]
On the other hand, depending on the size, material, and the like of the buffer member 2, the range of receiving the key pressing pressure on the contact surface with the sensor body 1 may be widened. When the spread is large, the width of the contact surface not receiving the key pressing pressure is reduced, or all of the contact surfaces receive the key pressing pressure of the operating portion of any key. Even in this case, the intermediate section N, which is an intermediate area between the contact positions of the adjacent operation parts on the buffer member, is separated from the position immediately below the impact position of the operation part. Since a portion and a width necessary for fixing the sensor main body 1 and the buffer member 2 are selected in the section N and set as an adhesive portion M, a large amount of key pressing pressure applied to the buffer member 2 is not received. The portion acts on the sensor body 1 through the sensing section P without the adhesive layer.
[0031]
In this way, all or a large part of the key pressing pressure applied to the buffer member 2 acts on the sensor body 1 through the sensing section P without the adhesive layer, so that the key pressing is performed through the adhesive layer. The trouble when pressure is transmitted is eliminated or reduced. That is, the adhesive layer tends to interpose and fix dust, air, flaws, etc., but there is no adhesive layer in the path that transmits all or many parts of the key pressing pressure, Their interposition and fixation are unlikely to occur. As a result, the fixation of distortion due to the presence of wrinkles is also eliminated or reduced. In addition, if there is such an interposition, a difference occurs in the shearing force generated by deformation through the adhesive layer, and there is a problem that the key pressing pressure is not properly transmitted, but there is no transmission through the adhesive layer or Since it is small, the generated shearing force itself is small. Therefore, even if these are present, the influence on the sensitivity of the pressure sensor is small.
[0032]
Furthermore, in transmission via an adhesive, when the adhesive becomes thicker and becomes plate-like or lump-like, that part has higher rigidity than the other parts, resulting in a difference in transmission rate and proper pressing. Although the key pressure cannot be transmitted, since the adhesive layer does not exist in the path for transmitting all or a large part of the key pressing pressure, the ratio of such a poor key pressing pressure transmission is small. As a result, accurate touch control can be realized without any trouble such as a variation in control performance depending on the key.
[0033]
FIG. 3 shows an example of a pressure sensor using the sensor body 1 and a multilayer buffer member 3. Since the thing of this example is common except the point from which the number of layers of a buffer member differs from the example of FIG. 1, description of a common point is abbreviate | omitted. The buffer member 3 in the example of FIG. 3 includes four layers of buffer members A1 to A4. In this example, the buffer member A1 is composed of white felt used in an acoustic piano, A2 is foamed resin material, A3 is red felt used in acoustic piano, and A4 is composed of foamed resin material. Here, the contact surface between the first layer A1 and the second layer A2 and the contact surface between the second layer A2 and the third layer A3 will be described. The first layer A1 of the buffer member is shown in a state where it receives a key pressing pressure at four locations in the figure. The key pressing pressure is transmitted to the contact surface with the second layer through the first layer A1.
[0034]
On the contact surface, the section N1 shows an intermediate area of the contact position on the buffer member of the adjacent operation part, and the other area shows a sensing section P1 for sensing the key pressing pressure by the sensor body 1. ing. In the intermediate section N1, adhesion is applied to a place necessary for adhesive strength, that is, a place necessary for fixing between the first layer and the second layer. In this example, a bonding portion M1 having a necessary width is formed in two necessary sections N1 among the three intermediate sections N1 shown in the drawing. Also on the contact surface between the second layer A2 and the third layer A3, the intermediate region of the contact position on the shock-absorbing member of the adjacent operation part is the intermediate section N2, and the other region is the key pressing pressure by the sensor body 1. The sensing period P2 is used for sensing. In the intermediate section N2, a bonding portion M2 is formed at a position necessary for bonding strength, that is, a position and width necessary for fixing between the second layer and the third layer.
[0035]
In this example, the contact surfaces between the third layer and the fourth layer and between the fourth layer and the sensor body 1 are bonded to the entire contact surface. Such a configuration is performed in the case where durability is given priority over a request for highly accurate touch control in which the same output can be obtained with the same key pressing force for all keys. Also in this case, the effect by providing the above-mentioned non-adhesion location in another layer can be acquired.
[0036]
As the key pressing pressure is transmitted to the first layer A1, the second layer A2, the third layer A3,... Therefore, a region where the key pressing pressure L is not transmitted or a small region on the contact surface with the layer becomes smaller as it is transmitted deeper into the layer. However, such an effect can be achieved by setting such a region as an intermediate section and further selecting a position and a width necessary for adhesive strength to form a bonded portion.
[0037]
FIG. 5 is a cross-sectional view of an example of a pressure sensor according to the second aspect of the present invention. This pressure sensor includes a sensor body 1 having a structure similar to that shown in FIG. As described above, various sensors can be used as the sensor body. A pair of gap forming members 4 are bonded to the upper surface of the sensor body 1 along both side edges thereof, and the buffer member 2 is bonded thereon.
[0038]
The gap forming member 4 can be formed of various materials such as plastic, rubber, and foams thereof, and is hard, elastic, or large in accordance with the sensitivity required for the sensor. Etc. are selected. The gap forming member can be formed of a material that is somewhat hard, or can be formed of a soft material. In the former case, if there is no elastic deformation of the buffer member, the gap forming member is formed of a material that does not elastically deform when pressed so that the buffer member does not contact the sensor main body, and the pressing force reaches the sensor main body. It is obtained mainly by deformation of the buffer member. In the latter case, the gap forming member is arranged so as to be elastically deformed in a direction substantially perpendicular to the pressure-sensitive surface of the sensor body when pressed, and the reaching of the pressing force to the sensor body is obtained mainly by deformation of the buffer member.
[0039]
For example, in the case where a polyester gap forming member 4 is provided on a sensor body 1 using a polyester film as a sensor constituting member 10 and a felt cushioning member 2 is provided, a sensor having the following dimensions can be obtained:
Sensor component 10: width 12 mm, thickness 0.1 mm,
Gap forming member 4: width 3 mm, thickness 0.2 mm,
Buffer member 2: 14 mm wide and 10 mm thick.
[0040]
In this sensor, when the pressing force is not applied, the buffer member is separated from the sensor main body. When the pressing force is applied, the buffer member is deformed and the lower surface is bent to contact the sensor main body and transmit the pressing force. Thus, since the buffer member 2 is mounted on the surface of the sensor main body 1 with the gap forming member 4 interposed therebetween, the inconvenience when the buffer member is directly bonded is eliminated. The buffer member may be fixed to the operating portion instead of being fixed to the sensor main body, and this is the same in the following embodiments.
[0041]
FIG. 6 includes, as the buffer member 5, a first buffer portion 5 a positioned on the sensor body side and a second buffer portion 5 b positioned on the operation portion side such as a key or its interlocking portion. The 1st buffer part 5a is comprised with the viscoelastic material which shows large deformation resistance, so that the pressing speed of an operation | movement part is large. As such a viscoelastic material, various materials exhibiting viscoelasticity such as a resin foam such as urethane foam (for example, trade name “Zulen” manufactured by Bridgestone Corporation) can be used. The second buffer member 5b is for buffering the contact of the operating portion with the first buffer member 5a to relieve the feeling of resistance when the key is depressed, and can be made of the various materials already described. . As described above, the buffer member 5 may be fixed to the operating portion, or may be separated, and the first buffer member 5a is fixed to the sensor body and the second buffer member 5b is fixed to the operating portion. Also good. Furthermore, when the buffering action by the first buffer member 5a is sufficient, the second buffer member 5b can be omitted.
[0042]
The sensor according to this embodiment operates as follows. During normal performance, the operating speed of the operating part is high and the shocking member 5 is shockedly contacted. Since the conventional buffer member is in direct contact with the surface of the sensor main body, the sensor senses an impact force when the operating portion comes into contact with the buffer member, and outputs a corresponding output. Also in the example shown in FIG. 5, when a normal buffer member such as felt is used, as shown in FIG. 7, shock contact by the operating portion is transmitted to the sensor body through the buffer member. The same phenomenon is shown. The original aftertouch control is to control the musical sound by intentionally changing the key pressing pressure applied after the key is stopped by pressing the key. Therefore, the fact that an output corresponding to the impact force when the operating part comes into contact with the buffer member itself is contrary to the purpose of the after touch control. In particular, in the case of a piano-type keyboard with a large mass, the impact force at the time of contact becomes strong, so this problem is great. In addition, since the sensor extends in the key arrangement direction and is shared by a plurality of keys, when a key belonging to the common sensor is pressed in addition to a key already pressed and in the after touch control state, A signal that senses the impact force of the sound is added, and an unintended musical sound is emitted during aftertouch control. It is conceivable that the output accompanying such an impact force is controlled by electrical signal processing such as passing through a low-pass filter. However, an electrical circuit for that purpose is required, which increases the manufacturing cost.
[0043]
On the other hand, in the sensor according to the embodiment shown in FIG. 6, the first buffer portion 5 a has a high viscosity so that the first buffer portion 5 a is deformed after the second buffer portion is deformed and contacts the sensor body 1 during the pressing force action. Made of elastic material. Therefore, with respect to the shocking contact (high-frequency contact pressure) at the time of the key stop described above, a rigid reaction force is shown without following the deformation. On the other hand, the pressing operation during after-touch control is slower than when the key is stopped, and such pressure (low frequency contact pressure) is deformed and bent following the pressure. Therefore, as shown in FIG. 6, when a gap is formed between the first buffer member 5a and the sensor main body 1 by the gap forming member 4, the first buffer member 5a against impact contact. Acts rigidly and is not easily deformed, and there is a gap t between the sensor body 1 and it does not reach, or even if it reaches, the transmitted pressure is small (see FIG. 8). On the other hand, for the press for after-touch control applied after the key is stopped, it is compressed following the press to bend while decreasing the thickness T, reaches the sensor body 1, and corresponds to the key pressing pressure. The pressing force is transmitted (see FIG. 9). This enables appropriate aftertouch control according to the player's intention. Further, when the key belonging to the common sensor is pressed in addition to the key already pressed and in the after touch control state, the first buffer member 5a shows a similar response to the impact force at the time of the subsequent key pressing. Therefore, in this case as well, it is possible to prevent a musical sound that is not intended. Such behavior of the first buffer member 5a is presumed to be as follows when viewed microscopically. The portion of the first buffer member located above the gap forming member and the portion in between are different in the deformation mode at the time of pressing. The former mainly causes compression deformation and the latter mainly causes bending deformation. Due to the properties of the viscoelastic material, both are difficult to deform against the high-frequency contact pressure described above. On the other hand, for the low-frequency contact pressure, the latter bending deformation occurs following the former compression deformation, and as a result, the first buffer member as a whole undergoes deformation following the contact pressure.
[0044]
Thus, since the impact force when the key is stopped is not transmitted to the sensor body as it is, the sensor body is prevented from being damaged by a large pressing force, and the service life can be extended. In particular, in the case of a highly sensitive sensor, since the durability against a large pressing force is often low, the effect is great.
[0045]
Next, the embodiment shown in FIG. 10 will be described. The gap forming member 4a of the sensor shown in FIG. 10 is composed of a pair of elongate members extending in the key arrangement direction at intervals. In the drawing, the buffer member bonded on the gap forming member 4a is omitted. The distance F between the pair of gap forming members 4a is narrow at the center C of the pressing position by the operating portion, and gradually changes so as to increase as the distance from the center increases. In this example, the interval F is the widest at the position farthest from the pressing position of the adjacent operating portions, that is, at the center D of the adjacent pressing positions. The degree of change in the distance F is determined in consideration of sensor sensitivity, the material of the gap forming member and the buffer member, and the like so as to achieve the operation described below. In this example, the sensor constituent member 10 having a width of 12 mm is used, the gap forming member 4 a is made of polyester and has a height of 0.25 mm, and the interval F changes from 4 mm at the narrowest portion to 8 mm at the widest portion. The buffer member is made of felt.
[0046]
This sensor operates as follows. The force L required to bend the buffer member 5 toward the sensor body 1 by the same amount is smaller as the gap F of the gap forming member 4 is larger (FIG. 11a) and larger as the gap is smaller (FIG. 11b). Further, the pressing force transmitted through the buffer member 5 is dispersed inside the buffer member, is greatest at a position immediately below the center of pressing, and decreases as the distance from the center of pressing decreases (FIG. 12). Therefore, when the buffer member 5 is in contact with the sensor body 1 in the vicinity of the pressing center as shown in FIG. 11a, the area of the pressing member 5 changes following the change of the pressing force sharply, but the pressing center as shown in FIG. When you leave, it will slow down. The change in the contact area between the buffer member and the sensor body corresponds to the change in the contact area between the electrode and the conductive member in the sensor body and is reflected in the sensor output. Therefore, when the gap forming member 4 is equally spaced, if the pressing force is increased to some extent, the boundary of the contact portion between the buffer member and the sensor main body becomes a position away from the pressing center, so the sensor output is Insensitive to changes in pressure. In consideration of this, in this example, the distance F between the buffer members 5 is reduced near the center of the press where a large pressing force acts, and the distance F between the buffer members 5 is increased at a position away from the center of the press and where the action of the pressing force is small. is doing. As a result, even if a large pressing force is applied, the contact portion between the buffer member and the sensor body can be kept near the pressing center, and the detection range of the pressure sensor for a large pressing force can be widened, and the output is output over the entire detection range. The characteristics can be made uniform.
[0047]
In the example shown in the figure, the buffer member includes the first buffer member 5a and the second buffer member 5b. However, a normal buffer member (for example, the one shown in FIG. 5) may be used. .
[0048]
FIG. 14 shows another example of the gap forming member used in the pressure sensor. The gap forming member 4b has a thin plate shape, and an opening 40 is formed at each position where a pressing force is applied by the operating portion. When forming the pressure sensor, the gap forming member 4b is bonded to the upper surface of the sensor body, and the buffer member is bonded to the gap forming member (in some cases, the buffer member may be fixed to the operating portion instead). The opening 40 is provided so that the buffer member can be bent by the pressing force and contact the sensor body through the opening. In the illustrated example, as described in the example of FIG. 10, the opening width G is small at a position close to the pressing center by the operating portion, and the opening width G is increased as the distance from the pressing center increases. Thereby, as described above, the detection range of the pressure sensor for a large pressing force can be widened, and the output characteristics can be made uniform over the entire detection range. However, when the required degree of the detection range is not so high, it is also possible to adopt a shape of the opening other than the above, such as a polygon or a circle. The size and size of the opening are determined according to the sensitivity of the pressure sensor, the material of the gap forming member 4b and the buffer member, and the like. In the illustrated example, the gap forming member 4b is made of polyester and has a height of 0.3 mm, and the gap g is 4 mm at the narrowest portion, 8 mm at the widest portion, and the length of the opening portion with respect to the sensor constituting member 10 having a width of 12 mm. The length (dimension in the longitudinal direction of the pressure sensor) is 9 mm, and the buffer member to be bonded thereon is made of felt.
[0049]
The pressure sensor using the gap forming member 4b operates as follows. FIG. 15 shows a portion along the longitudinal direction of the buffer member. When a pressing force L accompanying a key press is applied to a general buffer member 2, the pressing force is transmitted to the sensor constituent member with a pressure distribution indicated by q so that the pressing force is strong at the center of pressing and becomes weaker as it moves away from the bottom. . The base of this distribution curve often overlaps with each other due to adjacent motion parts. This can occur when the buffer member is directly bonded to the sensor body, and even when the buffer member is in contact with the sensor body via the gap forming member shown in FIGS. That can happen. There is a type of aftertouch control in which an independent sensor body is arranged for each key so that control can be performed for each key. In this case, if the buffer members are separated from each other, the manufacturing becomes complicated and the holding of the soft buffer members becomes unstable. Therefore, the buffer members are continuously extended over a plurality of keys. In this state, as described above, when there is an overlapping portion of the pressure distribution at the time of pressing, the pressure reaches the sensor body adjacent to the pressed sensor body. That is, the key other than the key-pressed part is affected, so-called crosstalk occurs, and independent aftertouch control for each key cannot be performed accurately. On the other hand, when the gap forming member 4b of FIG. 14 is used, the buffer member that has received the pressing force exerts pressure on the sensor body through the opening 40 of the gap forming member 4b, and is applied to portions other than the opening 4b of the buffer member. Even if the pressing force is distributed to the buffer member in contact therewith, the transmission is almost interrupted by the portion. Therefore, if the opening 4b is formed in accordance with the position of the independent sensor body, a pressing force can be accurately applied to each sensor body, and crosstalk can be prevented. That is, the gap forming member 4 blocks the pressing force acting on unnecessary portions other than the sensor main body to be operated. The pressing force may be transmitted to the sensor main body through the periphery of the opening 4b in the gap forming member 4, but this transmission force is clearer than the pressing force generated when the buffer member is in contact with the sensor main body. Since it shows a rise, it can be electrically removed by a low-pass filter. In addition, transmission through the periphery of the opening 4b can be prevented by adopting the form of the gap forming member described below.
[0050]
Next, the pressure sensor shown in FIG. 16 will be described. In this pressure sensor, the width of the gap forming member 4c varies depending on the position in the thickness direction. That is, the portion 41 near the sensor body 1 in the gap forming member 4c is composed of a pair of elongated portions that are narrow in width and extend in the key arrangement direction at intervals. On the other hand, the width of the portion 42 near the buffer member 5 is wider than the width of the portion near the sensor body. The gap forming member 4c is a thin plate having the opening shown in FIG. 14, and FIG. 16 shows a cross section of the opening of the gap forming member 4c. Thus, the sensor body portion 41 forms a stepped portion having a height h and reaches the buffer member portion 42. As described below, the width of the sensor body side portion 41 of the gap forming member 4c is determined so as not to cause a problem even if no pressure is applied to the sensor component member 10. The buffer member side portion 42 of the gap forming member 4c has a width as necessary from the viewpoint of supporting the buffer member 5 so that the sensor component member can be appropriately pressed.
[0051]
The pressure sensor using the gap forming member 4c operates as follows. When the gap forming member is in contact with the sensor component with the width of the portion that supports the buffer member, the width tends to be wide enough to transmit the pressing force to the pressure-sensitive portion of the sensor body. Therefore, the pressing force applied to the buffer member is transmitted not only from the buffer member but also through the gap forming member, and accurate aftertouch control cannot be performed. On the other hand, when the gap forming member 4c shown in FIG. 16 is used, since the portion 41 near the sensor body 1 is formed of a narrow and narrow portion, the pressing force is transmitted to the pressure sensitive portion of the sensor body. Is prevented. Further, the width of the portion 42 near the buffer member 5 is wider than the width of the portion near the sensor main body, and the width can be sufficient to support the buffer member. FIG. 17 is a perspective view of the gap forming member and the buffer member viewed obliquely from below. When the pressing force L acts on the buffer member 5, the buffer member 5 protrudes from the opening 40 of the gap forming member 4c. Shows the state. As can be understood from this figure, the pressing force is transmitted to the sensor constituent member by the buffer member protruding from the opening 40. On the other hand, the gap forming member 4c is in contact with the sensor constituent member at the narrow sensor body portion 41, so that the gap forming member is prevented from being pressed by the buffer member until the gap forming member is pressed. .
[0052]
FIG. 18 shows a gap forming member 4d approximated to FIG. In the gap forming member 4d, the sensor body side portion 43 has the same width as that of the above example, and the buffer member side portion 44 extends in the longitudinal direction of the member with a certain width necessary to support the buffer member. . In addition, the transition portion from the sensor body-side portion 43 to the buffer member-side portion 44 has a gentle curve. The pressure sensor using the gap forming member 4d also has the same function as the example of FIG.
[0053]
FIG. 19 shows an example in which the gap forming member 4e is accommodated in the case 6 that accommodates the sensor main body. The case 6 has a belt-like bottom wall 60 extending in the longitudinal direction of the sensor body and a pair extending on the bottom wall and extending in the longitudinal direction of the bottom wall. And an opposing wall 61 that forms an opening, and accommodates the sensor body 1. In this example, the gap forming member 4e is fixed on the opposing wall 61 of the case 6, and the buffer member 2 is bonded thereon. Similar to the above example, the portion 45 near the sensor body 1 in the gap forming member 4e is formed of a pair of narrow and narrow portions, and the buffer member close portion 44 is necessary for supporting the buffer member. It extends in the longitudinal direction of the member with a constant width. In this example, the pressing force applied to the buffer member deforms the buffer member to project downward from between the pair of gap forming members, and acts as a pressing force to the sensor constituent member. On the other hand, the pressing force transmitted from the buffer member to the gap forming member 4e is transmitted from the buffer member closer portion 45 having a width for supporting the buffer member to the opposing wall 61 of the case through the narrower sensor body closer portion 46. Therefore, there is almost no pressing force transmitted from the gap forming member to the sensor constituent member, and accurate aftertouch control can be realized.
[0054]
20 and FIG. 21, the sensor body side portion 41 of the gap forming member 4 c shown in FIG. 16 is in the sheet material thickness direction with respect to the spacer 11 between the pair of sheet-like sensor component members 10 in the sensor body. The state provided in the overlapping position is shown. 20 is a cross-sectional view of the pressure sensor, and FIG. 21 is a plan view showing the gap forming member 4e and the spacer 11 of the sensor body 1. As shown in FIG. 21, the pair of spacers 11 of the sensor main body has an inner edge that is narrow at the center of the pressing position by the operating portion, based on the same idea as described in the embodiment of FIG. 10. It gradually changes so as to become wider as it gets away from (indicated by a dashed line). FIG. 21 shows that the spacer-facing portion 41 of the gap forming member overlaps such a spacer 11. With this configuration, most of the pressing force transmitted from the buffer member 5 to the gap forming member 4e acts on the spacer 11 of the sensor body, so that it is prevented from being transmitted to the pressure-sensitive portion, and highly accurate aftertouch control is obtained. The position of the gap forming member near the sensor main body is determined according to the position of the spacer. When the spacer 11 is at both ends of the sensor main body 1 as shown in FIG. 42 is similarly positioned. In addition, in order to obtain this action, it is only necessary that the portion of the gap forming member closer to the sensor main body is provided so that the position overlaps with the spacer in the thickness direction of the sheet material.
[0055]
FIGS. 22 to 26 are vertical front views showing various modes in which a gap is formed between the sensor main body and a pressing member located on one of both sides in the pressing direction of the sensor body.
[0056]
FIG. 22 shows a pressure sensor in which the sensor body 1 and the buffer member 5 are supported by a rectangular case 6a having a substantially U-shaped cross section opened upward. The buffer member 5 includes a first buffer member 5a whose side wall is supported by the case 6a, and a second buffer member 5b fixed thereon. The first buffer member 5 a is supported by the case 6 a at a position where a gap is provided between the first buffer member 5 a and the upper surface of the sensor body 1. In this example, the side surface of the side wall of the case 6a functions as the gap forming member 4g.
[0057]
FIG. 23 has a structure similar to that shown in FIG. 22, but in this example, the first buffer member 5a is supported on the upper surface of the side wall of the case 6b, and the second buffer member is provided thereon. 5b is fixed. Also in this example, the side wall of the case 6b functions as the gap forming member 4g.
[0058]
In the pressure sensor shown in FIG. 24, the sensor body 1 is supported on a substrate 8, and a gap forming member 4i is fixed on the sensor body 1 with a space therebetween. A pressing member 7 is fixed on the gap forming member 4i, and a buffer member 5 is fixed thereon. The gap forming member 4i is arranged so as to be elastically deformed in a direction substantially perpendicular to the pressure-sensitive surface of the sensor body when receiving a pressing force. As the material, it is desirable to use a viscoelastic material having a large viscosity as described in FIGS. In other words, for impact contact (high frequency contact pressure) at the time of keystroke, it shows a rigid reaction force without following the deformation, and pressure (low frequency) due to a slow pressing operation during after touch control. It is preferable that the pressure is deformed and compressed in accordance with the contact pressure. As a result, as described above, it is possible to obtain an effect that it is possible to perform appropriate aftertouch control by eliminating the influence of the impact force when the key is stopped by the keystroke. Since the gap forming member is made of a material rich in viscoelasticity, the pressing member 7 is made of a material harder than this, and is supported by the gap forming member so as to leave a gap between the pressing member 7 and the sensor body 1.
[0059]
The pressure sensor shown in FIG. 25 has a structure similar to that shown in FIG. In this example, the pressing member 7 is fixed to the lower surface of the pressing plate 9 supported by the gap forming member 4j. Other configurations are the same as those in FIG.
[0060]
In the pressure sensor shown in FIG. 26, a gap forming member 4k disposed at an interval is supported at a lower portion of a rectangular case 6c having a substantially U-shaped cross section opened upward, and the sensor body 1 and the buffer member 5 are supported thereon. The pressing plate 9 and the buffer member 5 are fixed in this order. A pressing member 7 is supported between the gap forming members 4k on the bottom wall of the case 6c. The gap forming member 4k is made of the same material as that described with reference to FIG. 24, and is arranged so as to be elastically deformed in a direction substantially perpendicular to the pressure-sensitive surface of the sensor body when receiving a pressing force. The pressing member 7 is formed of a material harder than the gap forming member, and is supported by the gap forming member so as to leave a gap between the pressing member 7 and the sensor body 1.
[0061]
Each of the pressure sensors shown in FIGS. 22 to 26 is provided with a gap forming member so as to form a gap when not pressed with the pressing member located on one of both sides of the sensor body in the pressing direction. Yes. Therefore, the inconvenience due to the presence of foreign matters accompanying the adhesion to the buffer member sensor main body is eliminated, and accurate aftertouch control can be realized. In addition, when a viscoelastic material having a high viscosity is used as the gap forming member or the buffer member, it becomes possible to perform an appropriate after touch control by eliminating the influence of the impact force when the key is stopped by the keystroke. An effect can be obtained.
[0062]
【The invention's effect】
As described above, according to the first aspect of the present invention, intermittent partial bonding is performed in the key arrangement direction on the contact surface between the buffer member and the sensor body, and the partial bonding is performed between the adjacent operation parts. Since it is performed as a bond at a location necessary for the adhesive strength in the middle region of the contact position on the buffer member, the key pressing pressure is transmitted to the sensor body without being affected by the adhesive layer or by reducing the effect. can do. Accordingly, it is difficult to interpose dust, air, soot and the like, and even if intervened, the amount of shearing force transmitted by the adhesive layer itself is small, so the influence of inclusions is reduced. Moreover, the trouble that the adhesive layer becomes thick and becomes a plate or a lump and cannot transmit an appropriate key pressing pressure is eliminated or reduced. As a result, accurate touch control can be realized without any trouble such as the control performance varying depending on the key.
[0063]
When the buffer member is formed by stacking buffer members made of a plurality of layers (second invention), intermittent partial bonding is performed in the key arrangement direction on at least one contact surface of the layer. Adhesion is performed as adhesion at a position necessary for adhesive strength in an intermediate region of the contact position of the adjacent operation part on the buffer member. Similarly, troubles due to the intervention of the adhesive layer are eliminated or reduced. can do.
[0064]
Further, according to the third aspect of the present invention, the gap between the sensor body and the pressing member located on one of the both sides in the pressing direction of the sensor main body that receives the pressing force from the operating portion via the buffer member when not pressed. Since the gap forming member is provided so as to form the buffer, the buffer member is not directly bonded to the sensor body, and the inconvenience due to the presence of foreign matters due to such bonding is eliminated, and accurate aftertouch control is realized. can do.
[Brief description of the drawings]
FIG. 1 is a perspective view of a pressure sensor according to an embodiment of the first invention in the present invention.
2 is a longitudinal front view of the pressure sensor shown in FIG. 1. FIG.
FIG. 3 is a perspective view of a pressure sensor according to one embodiment of the second invention in the present invention.
FIG. 4 is a perspective view showing an example of an attachment position of a pressure sensor in a keyboard device.
FIG. 5 is a longitudinal front view of a pressure sensor according to an embodiment of the third invention in the present invention.
FIG. 6 is a longitudinal front view of a pressure sensor according to another embodiment of the third invention.
7 is a longitudinal front view showing a state of the pressure sensor shown in FIG.
8 is a longitudinal front view showing a state when an impact pressing force is applied to the pressure sensor shown in FIG. 6;
9 is a longitudinal front view showing a state when a pressing force for after-touch control of the pressure sensor shown in FIG. 6 is applied.
FIG. 10 is a perspective view of a pressure sensor according to still another embodiment of the third invention.
11 is an explanatory diagram of the operation of the pressure sensor shown in FIG.
12 is an explanatory diagram of a stress state of the pressure sensor shown in FIG.
13 is an explanatory diagram of the operation of the pressure sensor shown in FIG.
FIG. 14 is a perspective view of a gap forming member used in a pressure sensor according to still another embodiment of the third invention.
15 is an explanatory diagram of a stress state of a pressure sensor using the gap forming member shown in FIG.
FIG. 16 is a longitudinal front view of a pressure sensor according to still another embodiment of the third invention.
17 is a perspective view of a gap forming member and a buffer member in the pressure sensor shown in FIG. 16 as viewed obliquely from below.
FIG. 18 is a longitudinal front view of a pressure sensor according to still another embodiment of the third invention.
FIG. 19 is a longitudinal front view of a pressure sensor according to still another embodiment of the third invention.
FIG. 20 is a longitudinal front view of a pressure sensor according to still another embodiment of the third invention.
FIG. 21 is a plan view of a part of the pressure sensor shown in FIG. 20;
FIG. 22 is a longitudinal front view of a pressure sensor according to still another embodiment of the third invention.
FIG. 23 is a longitudinal front view of a pressure sensor according to still another embodiment of the third invention.
FIG. 24 is a longitudinal front view of a pressure sensor according to still another embodiment of the third invention.
FIG. 25 is a longitudinal front view of a pressure sensor according to still another embodiment of the third invention.
FIG. 26 is a longitudinal front view of a pressure sensor according to still another embodiment of the third invention.
FIG. 27 is a perspective view showing an example of a conventional pressure sensor.
FIG. 28 is a perspective view showing another example of a conventional pressure sensor.
FIG. 29 is a longitudinal sectional view showing an example of a defect of a conventional pressure sensor.
FIG. 30 is a longitudinal sectional view showing another example of a defect of a conventional pressure sensor.
FIG. 31 is an explanatory diagram of a defect of a conventional pressure sensor.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Sensor main body, 2, 3 ... Buffer member, 4, 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k ... Gap formation member, 5 ... Buffer member, 5a ... 1st buffer Members, 5b ... second buffer member, 10 ... sensor constituent member, 11 ... spacer, 41, 43, 45 ... part near the sensor body of the gap forming member, 42,43,44 ... part near the buffer member of the gap forming member, 6 ... Case, L ... Key-pressing pressure, N, N1, N2 ... Intermediate region of the abutting position on the shock-absorbing member of the adjacent operation part, M, M1, M2 ... Adhesion location, K ... Key, S ... Sensor body, A , A1, A2, A3, A4 ... cushioning member

Claims (11)

A shock-absorbing member that abuts with a buffering action and delimits a key-pressing stroke by a part of the key or a part of the member that interlocks with the key when the key is pressed, and a sensor for touch control that is disposed on the buffer member. A pressure sensor including a main body, wherein a partial adhesion is intermittently performed in a key arrangement direction on a contact surface between the buffer member and the sensor main body, and the partial adhesion is performed on the adjacent operation parts. touch pressure sensor of an electronic keyboard instrument, characterized by being conducted Oite in the middle region of the contact location on the cushioning member. A shock-absorbing member that abuts with a buffering action and delimits a key-pressing stroke by a part of the key or a part of the member that interlocks with the key when the key is pressed, and a sensor for touch control that is disposed on the buffer member. A pressure sensor including a main body, wherein the buffer member is formed by stacking a plurality of buffer members in layers, and intermittent partial adhesion is performed in the key arrangement direction on at least one contact surface between the layers. is and, partial adhesion is adjacent touch pressure sensor of the keyboard apparatus characterized by being performed Oite in the middle region of the contact position on the buffer member of the operation portion. An electronic keyboard instrument comprising a sensor main body that receives a pressing force via a buffer member from a movement part that is a part of a key or a part that interlocks with the key when the key is pressed, and that exhibits a sensor output corresponding to the pressing force. The pressure sensor for touch control, wherein the buffer member is disposed with a gap with respect to the sensor body via a gap forming member bonded to the sensor body. The reaching is performed based on deformation of the buffer member that is easier to deform than the gap forming member . An electronic keyboard instrument comprising a sensor main body that receives a pressing force via a buffer member from a movement part that is a part of a key or a part that interlocks with the key when the key is pressed, and that exhibits a sensor output corresponding to the pressing force. The pressure sensor for touch control, wherein the buffer member is disposed with a gap with respect to the sensor body via a gap forming member bonded to the sensor body. Reaching is performed based on deformation of the buffer member while accompanying elastic deformation of the gap forming member in a direction substantially perpendicular to the pressure sensitive surface of the sensor body . The pressure sensor according to claim 3 or 4, wherein a pressing member is fixed to the buffer member between the buffer member and the sensor body.   The gap forming members are provided so as to extend in the key arrangement direction with a space between each other, and the gap between the gap forming members is narrow at a position corresponding to the center of the pressing position by the operating portion, and the center corresponding position. The pressure sensor according to claim 3 or 4, wherein the pressure sensor gradually changes so as to become wider as the distance from the pressure sensor increases.   5. The pressure sensor according to claim 3, wherein the gap forming member has a thin plate shape and has an opening for each position to receive a pressing force by the operating portion.   The gap forming members are provided so as to extend in the key arrangement direction with a space between each other, and the width of each gap forming member varies depending on the position in the thickness direction. The pressure sensor according to claim 3, 4, 6, or 7, wherein an interval between the main body portions is wider than an interval between the buffer member portions.   The sensor body includes a sheet material having a pressure-sensitive function facing each other, and a spacer interposed between the sheet materials, and a portion closer to the sensor body of the gap forming member includes the spacer and the sheet material The pressure sensor according to any one of claims 3 to 8, wherein the pressure sensor is provided so as to overlap in the thickness direction.   The pressure sensor according to claim 3, wherein the gap forming member is formed by a part of a case that houses the sensor main body. A pressing member is disposed on the side opposite to the pressing force acting side of the sensor body, and a gap forming member is provided between the sensor body and the pressing member so as to form a gap when not pressed. 5. The pressure sensor according to claim 3, wherein the forming member is deformed in a direction substantially perpendicular to a pressure-sensitive surface of the sensor body when receiving a pressing force through the sensor body.

Images