U.S. patent application number 09/754780 was filed with the patent office on 2001-07-12 for jig for aligning shutter with photo couplers and key and assembling method using the same.
This patent application is currently assigned to Yamaha Corporation. Invention is credited to Itou, Katsuo, Tamaki, Takashi.
Application Number | 20010007218 09/754780 |
Document ID | / |
Family ID | 18530338 |
Filed Date | 2001-07-12 |
United States Patent
Application |
20010007218 |
Kind Code |
A1 |
Tamaki, Takashi ; et
al. |
July 12, 2001 |
Jig for aligning shutter with photo couplers and key and assembling
method using the same
Abstract
A jig is used in an assemblage between key sensors and an
acoustic piano, and the jig has a shutter guide assembled with a
casing of optical sensor array for aligning slits with target
trajectories of shutter plates and pieces of adhesive double coated
tape adhered to the shutter plates for aligning the shutter plates
with associated white/black keys, wherein the shutter plates are
inserted into the slits so that the shutter plates are placed on
the target trajectories, and the white/black keys are moved along
the target trajectories until they are brought into contact with
the pieces of adhesive double coated tape for temporality tacking
the shutter plates to the associated white/black keys.
Inventors: |
Tamaki, Takashi;
(Hamamatsu-shi, JP) ; Itou, Katsuo;
(Hamamatsu-shi, JP) |
Correspondence
Address: |
OSTROLENK FABER GERB & SOFFEN
1180 AVENUE OF THE AMERICAS
NEW YORK
NY
100368403
|
Assignee: |
Yamaha Corporation
|
Family ID: |
18530338 |
Appl. No.: |
09/754780 |
Filed: |
January 4, 2001 |
Current U.S.
Class: |
84/20 |
Current CPC
Class: |
G10G 3/04 20130101; G01V
8/20 20130101 |
Class at
Publication: |
84/20 |
International
Class: |
G10F 001/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 6, 2000 |
JP |
2000-1080 PAT |
Claims
What is claimed is:
1. A jig for aligning plural shutter members with associated
sensors and associated manipulators, comprising: a shutter guide
formed with plural hollow spaces snugly receiving said shutter
members, respectively, and having a positioning means for locating
said plural hollow spaces at target positions with respect to said
associated sensors; and temporal tacking means provided on said
plural shutter members for temporality tacking said plural shutter
members to said associated manipulators.
2. The jig as set forth in claim 1, in which said associated
manipulators are keys forming parts of a keyboard musical
instrument.
3. The jig as set forth in claim 2, in which said keyboard musical
instrument is an acoustic piano.
4. The jig as set forth in claim 1, in which said shutter guide
includes a pair of sheet members defining said hollow spaces at the
boundary therebetween.
5. The jig as set forth in claim 4, in which said sheet members
respectively have edges each periodically projecting so that said
edges define said hollow spaces when said sheet members are
assembled together.
6. The jig as set forth in claim 5, in which said edges form
rectangular projections, and the leading ends of said rectangular
projections formed in one of said sheet members are shorter than
the distance between said rectangular projections formed in the
other of said sheet members.
7. The jig as set forth in claim 5, in which said edges form
right-angled triangular projections, and a base of each
right-angled triangular projection is shorter than a distance
between adjacent two of said right-angled triangular
projections.
8. The jig as set forth in claim 1, in which said positioning means
is implemented by stem portions of bolts and recesses formed in
said shutter guide for receiving said step portions.
9. The jig as set forth in claim 1, in which said shutter guide is
formed of paper.
10. The jig as set forth in claim 9, in which said shutter guide is
formed from a sheet of cardboard of said paper.
11. The jig as set forth in claim 1, in which said temporal tacking
means are pieces of adhesive compound coated on said shutter
members, respectively.
12. The jig as set forth in claim 11, in which said pieces of
adhesive compound are adhesive layers of sheets of adhesive double
coated tape.
13. The jig as set forth in claim 1, further comprising a
reinforcing plate and a separator extending one surface of said
reinforcing plate for smoothly separating said temporal tacking
means on said plural shutter members from said reinforcing
plate.
14. The jig as set forth in claim 13, in which said separator and
said temporal tacking means on said plural shutter members are
sandwiched between said reinforcing plate and said shutter guide so
that said plural shutter members respectively projects through said
hollow spaces.
15. A method for assembling a detector array and shutter members
with a keyboard musical instrument having a stationary member and
plural manipulators movable with respect to said stationary member,
comprising the steps of: a) preparing a jig having a shutter guide
and temporal tacking means; b) mounting said detector array on said
stationary member; c) aligning said shutter members with the
detectors of said array by using said shutter guide; d) temporality
tacking said shutter members to said plural manipulators by using
said temporal tacking means for aligning said shutter members with
said plural manipulators; and e) fixing said shutter members to
said plural manipulators, respectively.
16. The method as set forth in claim 15, in which said step c)
includes the sub-steps of c-1) assembling said shutter guide with
said detector array so as to locate hollow spaces formed in said
shutter guide on target trajectories of said shutter members, and
c-2) putting said shutter members on said shutter guide in such a
manner as to cause parts of said shutter members to project through
said hollow spaces, respectively.
17. The method as set forth in claim 15, in which said step d)
includes the sub-steps of d-1) attaching said temporal tacking
means to said shutter members put on said shutter guide in such a
manner as to cause parts of said shutter members to project through
hollows spaces formed in said shutter guide, and d-2) moving said
plural manipulators along target trajectories so as to bring said
plural manipulators into contact with said temporal tacking means,
thereby temporarily tacking said shutter members to said plural
manipulators, respectively.
18. The method as set forth in claim 15, in which said jig further
has a reinforcing plate and a separator sandwiched between said
reinforcing plate and said shutter guide together with said
temporal tacking members adhered to said shutter members partially
projecting through hollow spaces formed in said shutter guide.
19. The method as set forth in claim 18, in which said step c)
includes the sub-steps of assembling said shutter guide with said
detector array so as to locate said shutter members projecting
through said hollow spaces on target trajectories of said shutter
members.
20. The method as set forth in claim 18, in which said step d)
includes the sub-steps of d-1) separating said separator adhered to
said reinforcing member from said temporal tacking means so that
said shutter members and said temporal tacking means are left on
said shutter guide, and d-2) moving said plural manipulator along
target trajectories so as to be brought into contact with said
temporal tacking means.
Description
FIELD OF THE INVENTION
[0001] This invention relates to a keyboard musical instrument
equipped with key sensors and, more particularly, to a jig for
aligning a shutter plate with a key and an assembling method using
the jig.
DESCRIPTION OF THE RELATED ART
[0002] Various kinds of keyboard musical instrument are sold in the
market. An automatic player piano is categorized in the keyboard
musical instrument. The automatic player piano is an acoustic piano
equipped with a playback system and a recording system. The
playback system includes solenoid-operated key actuators and a
controller. The solenoid-operated key actuators are provided on the
key bed under the keyboard, and the controller sequentially
energizes the solenoid-operated key actuators for moving the keys
without fingering. The keys are moved as if a pianist plays a tune
on the keyboard. On the other hand, the recording system includes a
data processor and key sensors attached to the white keys and the
black keys. While a pianist is fingering on the keyboard, the
white/black keys are selectively moved for actuating associated
action mechanisms. The action mechanisms give rise to rotation of
hammers, and the hammers strike associated music strings. The key
sensors are provided on the trajectories of the white/black keys,
and notify the key motions to the data processor. The data
processor analyzes the pieces of positional data information for
the key velocity and timings, and produces music data codes
representative of the performance on the keyboard.
[0003] A known key sensor is a combination of a shutter plate and
photo-couplers. The shutter plate is attached to a lower surface of
the associated white/black key, and downwardly projects therefrom.
Thus, the shutter plate is movable together with the white/black
key. On the other hand, the photo-couplers are provided on the key
bed, and radiate light beams across the trajectory of the shutter
plate. While a pianist is depressing the white/black key from the
rest position toward the end position, the shutter plate
sequentially interrupts the light beams. The photo-couplers notify
the interruptions to the data processor. The data processor
determines lapse of time from the initiation of the performance to
the interruption of the light beam, and calculates the key velocity
on the basis of the time period between the interruption of the
upper light beam and the interruption of the lower light beam.
Thus, the key sensors are important parts of the automatic player
piano, and the manufacturer assembles the shutter plates and the
photo-couplers with the keys and the key bed, respectively.
[0004] Conventionally, the shutter plates are manually attached to
the white/black keys. If a shutter plate is offset from the target
position, the shutter plate does not interrupt the light beams. For
this reason, the assembling worker is expected to carefully
assembly the shutter plates to the white/black keys. Such a careful
work consumes a large amount of time and labor, and increases the
production cost of the automatic player piano.
[0005] In order to speed up the assembling work, a jig is proposed
in Japanese Patent Publication of Unexamined Application
(laid-open) No. 3-154097. The prior art jig disclosed in the
Japanese Patent Publication of Unexamined Application includes a
spacer and an adhesive double coated tape. The photo-couplers are
fixed to a cubic case, and a slit is formed in the cubic case. The
cubic case is associated with one of the keys. Plural cubic cases
are arrayed, and the case array is to be mounted on the key bed.
The slit is open to the upper surface of each cubic case, and
downwardly penetrates from the upper surface. A pair of
photo-couplers is fixed inside the cubic case in such a manner as
to radiate the light beams across the slit. The slit is wider than
the shutter plate, and the shutter plate is insertable into the
slit.
[0006] The prior art jig has a base plate to be placed on the upper
surface of the cubic case and a vertical plate snugly received in
the slit of the cubic case. A narrow slit is formed in the vertical
plate, and is open to the upper surface of the base plate. The
narrow slit is as wide as the shutter plate. The key sensor is
assembled as follows. The array of cubic cases is mounted on the
key bed, and the cubit cases are roughly aligned with the
associated keys. The prior art jig is placed on one of the cubic
cases, and the vertical plate is snugly inserted into the slit
formed in the cubic case. The shutter plate is placed on the prior
art jig, and is snugly received in the slit formed in the vertical
plate. A piece of the adhesive double coated tape is adhered to the
upper surface of the shutter plate. The associated key is
downwardly moved, and the piece of double coated tape is adhered to
the lower surface of the associated key. The shutter plate is fixed
to the associated key by means of nails. The above-described
assembling work is repeated for all the keys.
[0007] The prior art jig makes the shutter plate exactly aligned
with the associated key, and permits the manufacturer to complete
the assembling work speedy. However, the prior art jig is used for
the alignment of each shutter plate with the associated key. This
means that the manufacturer needs to move the prior art jig from
one cubic case to another. For this reason, the assembling work
still consumes a large amount of time and labor, and the production
cost is not so widely reduced.
SUMMARY OF THE INVENTION
[0008] It is therefore an important object of the present invention
to provide a jig, which concurrently aligns plural shutter plates
with associated keys.
[0009] It is also an important object of the present invention to
provide an assembling method using the jig.
[0010] In accordance with one aspect of the present invention,
there is provided a jig for aligning plural shutter members with
associated sensors and associated manipulators comprising a shutter
guide formed with plural hollow spaces snugly receiving the shutter
members, respectively, and having a positioning means for locating
the plural hollow spaces at target positions with respect to the
associated sensors, and temporal tacking means provided on the
plural shutter members for temporality tacking the plural shutter
members to the associated manipulators.
[0011] In accordance with another aspect of the present invention,
there is provided a method for assembling a detector array and
shutter members with a keyboard musical instrument having a
stationary member and plural manipulators movable with respect to
the stationary member comprising the steps of a) preparing a jig
having a shutter guide and temporal tacking means, b) mounting the
detector array on the stationary member, c) aligning the shutter
members with the detectors of the array by using the shutter guide,
d) temporality tacking the shutter members to the plural
manipulators by using the temporal tacking means for aligning the
shutter members with the plural manipulators, and e) fixing the
shutter members to the plural manipulators, respectively.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The features and advantages of the jig and the assembling
method will be more clearly understood from the following
description taken in conjunction with the accompanying drawings in
which:
[0013] FIG. 1 is a perspective view showing a key sensor to which
the present invention appertains;
[0014] FIG. 2 is a perspective view showing a shutter guide split
into two plates;
[0015] FIG. 3 is a plane view showing the two plates assembled
together;
[0016] FIG. 4 is a plane view showing the shutter guide attached to
a casing of an optical sensor array;
[0017] FIG. 5 is a perspective view showing the shutter guide
attached to the casing;
[0018] FIG. 6 is a cross sectional view showing white/black keys
pressed against pieces of adhesive double-coated tape;
[0019] FIG. 7 is a cross sectional view showing another shutter
guide according to the present invention.
[0020] FIG. 8 is a plane view showing yet another shutter guide
according to the present invention; and
[0021] FIG. 9 is a plane view showing still another shutter plate
according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] First Embodiment
[0023] Referring to FIG. 1 of the drawings, a white key 1 is lifted
over a key bed 14. A front rail and a balance rail laterally extend
on the key bend 14, and a gap takes place between the front rail 12
and the balance rail 13. The white key 1 forms a keyboard together
with other white keys and black keys, and the keyboard is
incorporated in an acoustic piano. Eighty-eight white/black keys 1
are lain on the well-known keyboard pattern. Key sensors are
associated with the white/black keys 1, respectively, and plural
shutter plates 11 and an optical sensor array 15 constitute the key
sensors. Only one of the shutter plates 11 is shown in FIG. 1, and
the optical sensor array 15 is shared between the plural shutter
plates 11.
[0024] The shutter plate 11 is to be fixed to the lower surface of
the white key 1, and the optical sensor array 15 is mounted on the
key bed 14 between the front rail 12 and the balance rail 13.
Though not shown in FIG. 1, a piece of adhesive double coated tape
is to be inserted between the shutter plate 11 and the lower
surface of the white key 1, and the shutter plate 11 is fixed to
the white key 1 by means of U-letter shaped tacks.
[0025] The shutter plate 11 has a boss portion 11a and a tongue
11b. A pair of holes is formed in the boss portion 11a, and the
holes are spaced from each other. The piece of adhesive double-
coated tape is adhered to the boss portion 11a between the holes,
and the U-letter shaped tacks are driven through the holes into the
white key 1. The tongue 11b downwardly projects from the boss
portion 11a, and is movable together with the associated
white/black keys 11.
[0026] The optical sensor array 15 includes a casing and
photo-couplers PC accommodated in the casing. Plural base plates 16
are fixed to the key bed 14, and are laterally spaced from one
another at intervals. The casing laterally extends over the key bed
14, and is fixed to the plural base plates 16. The casing is as
long as the keyboard, and the casing is shared between the shutter
plates 11 attached to the white/black keys 11. A wide channel
member 15b and a narrow channel member 15c are assembled in such a
manner as to form a hollow space S therebetween.
[0027] Slits 15a are formed in the narrow channel member 15c at
intervals equal to those of the shutter plates 11 attached to the
white/black keys 11. The slits 15a are wider than the tongues 11b,
and the tongues 11b are moved into and out of the hollow space S
through the associated slits 15a. The photo-couplers are provided
in the hollow space, and radiate light beams across the
trajectories of the tongues 11b, respectively. Plural
photo-couplers PC are arranged along the trajectory of each
white/black key 11. While a white/black key 11 is being downwardly
moved, the tongue 11b sequentially interrupts the light beams of
the associated photo-couplers PC, and the photo-couplers PC notify
the current position of the associated white/black key 11 to a data
processor (not shown).
[0028] The wide channel member 15b has fins 15d sideward projecting
from both sides, and pairs of holes are formed in the fins 15d.
Pairs of spring brackets 16a upwardly project from the base plates
16. The spring brackets 16a of each pair are spaced apart from each
other in the fore-and-aft direction, and the distance between the
spring brackets 16a of each pair are equal to the distance between
the holes of the associated pair. The spring bracket 16a has a
column and delta wings. The delta wings are spread from an
intermediate portion of the column to the base plate 16. A female
screw is vertically tapped in the column. The wide channel member
15b is placed on the base plates 16, and the holes are aligned with
the columns of the spring brackets 16a, respectively. Coil springs
16b are received by the spring brackets 16a, respectively. The
delta wings space the coil springs 16b from the base plates 16, and
cause the upper ends of the coil springs 16b to upwardly project
from the columns. Bolts 17 respectively pass the holes, and are
screwed into the columns of the spring brackets 16a. The fins 15d
exert force on the coil springs 16b, and the coil springs 16b are
compressed. A worker appropriate regulates the force exerted on
each of the coil springs 16b so as to keep the upper surface of the
casing 15b/15c spaced from the key bed 14 by a predetermined
distance. Accordingly, the photo-couplers PC are adjusted to
appropriate positions with respect to the shutter plates 11 in the
rest positions. Even if the key sensors 11/15 are installed in an
acoustic piano at user's home, the worker easily adjusts the
photo-couplers PC to the appropriate positions.
[0029] FIGS. 2, 3, 4, 5 and 6 show a jig according to the present
invention. The jig is used for alignment between shutter plates 11
and the optical sensor array 15 and between the shutter plates 11
and the associated white/black keys 1. The jig according to the
present invention comprises a shutter guide 21/22 (see FIGS. 2 to
5) and pieces of adhesive double coated tape 30 (see FIG. 6). The
shutter guide 21/22 has a generally rectangular shape, and is
laterally elongated under the white/black keys 1. In this instance,
the shutter guide 21/22 are divided into four sub-guides. Each of
the sub-guides is used for twenty-two white/black keys 1, because a
monolithic structure is too long to be handled by a worker.
[0030] The shutter guide is split into two plates 21 and 22 (see
FIG. 2). The plates 21/22 are, by way of example, formed from a
sheet of cardboard. The cardboard is economical, and is easily
recycled. The plate 20 has an inner edge 20a, which projects at
intervals in such a manner as to form rectangular portions.
Similarly, the other plate 21 has an inner edge 21a forming
rectangular portions at intervals. Recesses take place between the
rectangular portions of the plate 20, and the other plate 21 also
has recesses between the rectangular portions. The rectangular
portions of the plate 20 are to be inter-digitated with the
rectangular portions of the other plate 21. However, the recesses
are wider than the rectangular portions. For this reason, when the
plates 20 and 21 are assembled together, slits 23 are formed
between the side edges of the rectangular portions of the plate 20
and the associated side edges of the rectangular portions of the
other plate 21 as shown in FIG. 3. The slits 23 are narrower than
the slits 15a (see FIG. 4), and are as narrow as the associated
tongues 11b. The inner edges 20a/21a may be formed by using a
punching machine. A Thomson die is available for the punching, and
the Thomson die reduces the machining cost.
[0031] Semi-circular recesses 20b and 21b are further formed in the
outer portions of the plates 20 and 21, and serve as indexing
notches. The bolts 17 are snugly received in the semi-circular
recesses 20b/21b, and cause the slits 23 to be nested in the slits
15a. Thus, the bolts 17 and the recesses 20b/21b align the slits 23
with the central portions of the slits 15a. When the tongues 11b of
the shutter plates 11 are inserted into the slits 23, the tongues
11b are exactly aligned with the associated photo-couplers PC.
[0032] The pieces 30 of adhesive double coated tape are adhered
between the upper surfaces of the boss portions 11a and the lower
surfaces of the white/black keys 1, and temporality tack the
shutter plates 11 to the white/ black keys 1.
[0033] Using the jig according to the present invention, the key
sensors 11/15 are assembled with the acoustic piano as follows. The
acoustic piano is assumed to have been already placed at user's
home. First, a worker lifts up the white/black keys 1 as shown in
FIG. 1. The front rail 12 and the balance rail 13 are exposed to
the worker, and the base plates 16 are fixed to the key bed 14 at
intervals. The spring brackets 16a are upright on the base plates
16.
[0034] Subsequently, the coil springs 16b are put onto the columns
of the spring brackets 16a, respectively. The narrow channel member
15c has been assembled with the wide channel member 15b on which
the photo-couplers PC were installed. The optical sensor array 15
is put on the base plates 16, and the holes are aligned to the
columns of the spring brackets 16b. The bolts 17 are inserted into
the holes, and are engaged with the female screws of the columns.
The bolts 17 are screwed into the spring brackets 16b against the
elastic force of the coil springs 16b. The worker makes the upper
surface of the narrow channel member 15c roughly parallel to the
lower surfaces of the white/black keys 1 by regulating the force
exerted on the coil springs 16b.
[0035] Subsequently, the plates 20/21 are assembled together as
shown in FIG. 3, and put on the optical sensor array 15. The
shutter guide 20/21 is adjusted in such a manner that the stem
portions of the bolts 17 are placed in the semi-circular recesses
20b/21b. The worker turns the bolts 17, and makes the shutter guide
20/21 parallel to the lower surfaces of the white/black keys 1. The
bolt heads are pressed against the shutter guide 20/21. Then, the
shutter guide 20/21 is fixed to the casing, and the slits 23 are
properly nested in the slits 15a as shown in FIG. 4.
[0036] Subsequently, the tongues 11b is inserted into the slits 23,
and the boss portions 11a are put on the shutter guide 20/21. The
shutter places 11 are aligned with the associated photo-couplers PC
of the optical sensor array 15. The pieces of adhesive double
coated tape 30 are put on the upper surfaces of the boss portions
11a. The white/black keys 1 are put on the balance rail 13, and
balance pins 13a and front pins 12a are inserted into the
associated white/black keys 1. The white/black keys 1 are inclined
due to the self-weight, and the front end portions of the
white/black keys 1 are spaced from front pin cloth punchings
12b.
[0037] Subsequently, the worker depresses the white/black keys 1,
and are pressed against the pieces of adhesive double coated tape
30 as shown in figure 6. The shutter plates 11 are temporality
tacked to the lower surfaces of the white/black keys 1 by means of
the pieces of adhesive double coated tape 30. Thus, the shutter
plates 11 are aligned with the associated white/black keys 1,
respectively, without moving the shutter guide 20/21.
[0038] The worker disassembles the white/black keys 1 from the
balance rail 13 and the front rail 12, and the shutter plates 11
are fixed to the white/black keys 1 by means of U-letter shaped
tacks (not shown). The worker removes the shutter guide 20/21 from
the optical sensor array 15, and regulates the bolts 17 so as to
adjust the optical sensor array 15 to the predetermined height.
Finally, the worker inserts the balance pins 13a and the front pins
12a into the white/ black keys 1, again. The tongues 11b are
aligned with the slits 15a, and the assemblage is completed.
[0039] In the first embodiment, the white/black keys 1 are
corresponding to plural manipulators, and the bolts 17 and the
semi-circular recesses 20b/21b as a whole constitute a positioning
means. The slits 23 are equivalent to hollow spaces, and the pieces
of adhesive double coated tape 30 serve as temporal tacking means.
The optical sensor array 15 is corresponding to a detector array,
and the key bed 14 serves as a stationary member.
[0040] As will be appreciated from the foregoing description, the
plural slits 23 are formed in the shutter guide 20/21, and are
simultaneously aligned with the slits 15a of the optical sensor
array 15 when the shutter guide 20/21 is appropriately positioned
on the casing 15b/15c of the optical sensor array 15. The tongues
11b are snugly received in the slits 23, and the shutter guide
20/21 permits the worker to align the shutter plates 11 with the
associated photo couplers PC. The pieces of adhesive double coated
tape 30 temporality tack the shutter plates 11 already aligned with
the photo couplers PC to the associated white/black keys 1, and the
shutter plates 11 are aligned with the associated white/black keys
1. The above-described aligning works are carried out without
moving the shutter guide 20/21. Thus, the shutter guide 20/21 makes
the assemblage simple and easy. This results in reduction of
assembling cost.
[0041] Second Embodiment
[0042] FIG. 7 shows another jig 60 embodying the present invention.
The jig 60 implementing the second embodiment comprises the shutter
guide 20/21, the pieces of adhesive double coated tape 30, a
separator 90 and a reinforcing plate 91. The shutter guide 20/21
and the pieces of adhesive double coated tape 30 are similar to
those of the first embodiment, and no further description is
incorporated hereinbelow.
[0043] The reinforcing plate 91 is formed of paper such as a sheet
of cardboard. The separator 90 is provided between the reinforcing
plate 91 and the pieces of adhesive double coated tape 30, and
allows a worker to smoothly separate the pieces of adhesive double
coated tape 30. The reinforcing plate 91 enhances the mechanical
strength of the shutter guide 20/21, and prevents the shutter guide
20/21 from undesirable deformation during the conveyance of the jig
60.
[0044] The key sensors are installed in the acoustic piano as
follows. The manufacturer assembles the plates 20/21 into the
shutter guide, and inserts the shutter plates 11 into the slits 23.
The pieces of adhesive double coated tape 30 are adhered to the
boss portions 11a of the shutter plates 11, respectively, and the
separator 90 is adhered to the reinforcing plate 91. The pieces of
adhesive double coated tape 30 are adhered to the separator 90.
Thus, the shutter plates 11 are sandwiched between the shutter
guide 20/21 and the reinforcing plate 91 as shown in FIG. 7. The
assemblage between the shutter plates 11 and the jig 60 is carried
out in a factory of the manufacturer or a service station of a
seller.
[0045] A worker conveys the optical sensor array 15 and the shutter
plates 11 already assembled with the jig 60 to user's home. The
worker lifts up the white/black keys 1 as shown in FIG. 1. The
front rail 12 and the balance rail 13 are exposed to the worker,
and the base plates 16 are fixed to the key bed 14 at intervals.
The spring brackets 16a are upright on the base plates 16.
[0046] Subsequently, the coil springs 16b are put onto the columns
of the spring brackets 16a, respectively. The optical sensor array
15 is put on the base plates 16, and the holes are aligned to the
columns of the spring brackets 16b. The bolts 17 are inserted into
the holes, and are engaged with the female screws of the columns.
The bolts 17 are screwed into the spring brackets 16b against the
elastic force of the coil springs 16b. The worker makes the upper
surface of the narrow channel member 15c roughly in parallel to the
lower surfaces of the white/black keys 1 by regulating the force
exerted on the coil springs 16b.
[0047] Subsequently, the shutter guide 20/21 is put on the casing,
and the semicircular recesses 20b/21b are aligned with the stems of
the bolts 17. The tongues 11b are inserted into the slits 15a, and
are aligned with the photo-couplers PC. The worker screws the bolts
into the spring brackets 16a, and fixes the shutter guide 20/21 to
the casing of the optical sensor array 15.
[0048] The white/ black keys 1 are put on the balance rail 13, and
balance pins 13a and front pins 12a are inserted into the
associated white/black keys 1. The white/black keys 1 are inclined
due to the self-weight, and the front end portions of the
white/black keys 1 are spaced from front pin cloth punchings
12b.
[0049] Subsequently, the worker depresses the white/black keys 1.
The lower surface of the white/black keys 1 are brought into
contact with the upper surface of the reinforcing plate 91. The
worker checks the white/black keys 1 to see whether or not gap
takes place between the lower surfaces of the white/black keys 1
and the reinforcing plate 91. If the reinforcing plate 91 is
inclined, the gap takes place. Then, the worker regulates the bolts
17 so as to make the lower surfaces of the white/black keys 1 in
parallel to the upper surface of the reinforcing plate 91. Thus,
the reinforcing plate 91 assists the worker in making the lower
surfaces of the white/black keys 1 in parallel to the pieces of
adhesive double coated tape 30 without adhesion to the white/black
keys 1. The white/black keys 1 are removed from the center rail 13,
again.
[0050] Subsequently, the worker separates the reinforcing plate 91
together with the separator 90 from the pieces of adhesive double
coated tape 30. The white/black keys 1 are put on the center rail
13, and the worker presses the white/black keys 1 against the
pieces of adhesive double coated tape 30. The shutter plates 11 are
temporality tacked to the lower surfaces of the white/black keys 1
by means of the pieces of adhesive double coated tape 30. Thus, the
shutter plates 11 are aligned with the associated white/black keys
1, respectively, without moving the shutter guide 20/21.
[0051] The worker disassembles the white/black keys 1 from the
balance rail 13 and the front rail 12, and the shutter plates 11
are fixed to the white/black keys 1 by means of U-letter shaped
tacks (not shown). The worker removes the shutter guide 20/21 from
the optical sensor array 15, and regulates the bolts 17 so as to
adjust the optical sensor array 15 to the predetermined height.
Finally, the worker inserts the balance pins 13a and the front pins
12a into the white/ black keys 1, again. The tongues 11b are
aligned with the slits 15a, and the key sensors are installed in
the acoustic piano.
[0052] As will be appreciated from the foregoing description, the
jig 60 assists the worker in assembling the key sensors with the
acoustic piano. The plural shutter plates 11 are simultaneously
aligned with the associated photo couplers PC and, thereafter, with
the associated white/black keys 1. Thus, the jig according to the
present invention accelerates the assemblage between the optical
sensor array and the shutter plates 11 and between the shutter
plates 11 and the white/black keys 1. In the second embodiment, the
shutter plates 11 are sandwiched between the shutter guide 20/21
and the reinforcing plate 91 in the factory or the service station.
This results in speed-up of the assembling work at user's home.
[0053] Although particular embodiments of the present invention
have been shown and described, it will be apparent to those skilled
in the art that various changes and modifications may be made
without departing from the spirit and scope of the present
invention.
[0054] Yet another shutter guide 70 may be formed from a monolithic
plate as shown in FIG. 8. The monolithic plate is formed from a
sheet of cardboard, and slits 23 and semi-circular recesses 21b are
formed in the monolithic plate. The slits 23 are equal in width to
or less than 1 millimeter, and the tongues 11b are snugly received
in the slits 23. The slits 23 and the semi-circular recesses 21b
may be formed by using a punching machine. However, a machining
cost is higher than that of the first embodiment, because the fine
blanking requires a fine die.
[0055] Still another pair of plates 80/81 may form yet another
shutter guide according to the present invention as shown in FIG.
9. The plates 80/81 respectively have inner edges 80a/80b like
saw-tooth. For this reason, the inner edges 80a/80b form triangular
projections. When the plates 80/81 are assembled, the triangular
projections are slightly offset from each other, and form slits
23.
[0056] A casing may have projections which are to be inserted into
holes formed in a shutter guide according to the present invention.
In this instance, the bolts 17 are not used for the
positioning.
[0057] The relative position between the semi-circular recesses 21b
and the slits 23 is identical with the relative position between
the bolts 17 and the slits 15a. For this reason, when the shutter
guide 70 is fixed to the casing by means of the bolts 17, the slits
23 are aligned with the slits 15a. The shutter guide 70 is formed
from the monolithic plate, and a worker can fix the shutter guide
70 to the casing without the assemblage.
[0058] The shutter guide 20/ 21, 60, 70 and 80 may be formed of any
kind of material such as, for example, wood, metal, alloy or
synthetic resin.
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