CA1162429A - Gong striking mechanism - Google Patents
Gong striking mechanismInfo
- Publication number
- CA1162429A CA1162429A CA000368325A CA368325A CA1162429A CA 1162429 A CA1162429 A CA 1162429A CA 000368325 A CA000368325 A CA 000368325A CA 368325 A CA368325 A CA 368325A CA 1162429 A CA1162429 A CA 1162429A
- Authority
- CA
- Canada
- Prior art keywords
- gong
- hammer
- cam
- motor
- striking
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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- Transmission Devices (AREA)
Abstract
GONG STRIKING MECHANISM
Abstract of the Disclosure A gong striking mechanism is provided, which comprises an electric motor mounted on a frame within a gong. A
conversion unit is rotationally connected directly or indirectly to the motor shaft for converting continuous rotational motion to reciprocal gong striking motion.
Resilient elements are provided to absorb impact forces during the gong striking motion and are disposed between the motor and a hammer.
Abstract of the Disclosure A gong striking mechanism is provided, which comprises an electric motor mounted on a frame within a gong. A
conversion unit is rotationally connected directly or indirectly to the motor shaft for converting continuous rotational motion to reciprocal gong striking motion.
Resilient elements are provided to absorb impact forces during the gong striking motion and are disposed between the motor and a hammer.
Description
~ i2~
This invention relates to an electric bell of the type which is driven by a motor and adapted for use in a fire bell, an alarm bell or the like, and more particularly to a gong striking mechanism driven by a motor to strike a gong.
Prior art electric bells have had the drawback of having a rotating pivot plate connected to a motor shaft.
The pivot plate has a counter-weight at one end and a striking hammer at the other. The pivot plate cannot be perfectly balanced and consequently fluctuates during the striking of the gong. As a result, the motor shaft either bends due to the large torque to which it is subjected or the pivot plate falls off the shaft because it cannot properly be secured thereto.
One prior art configuration attempts to overcome this situation, however t it requires complex and expensive parts.
Accordingly, it is an object of this invention to provide a novel gong striking mechanism in which the above-described drawbacks accompanying a conventional electric bell are overcome. Another object of the invention is to provide a mechanism in which reliable and simple parts may be employed to eliminate difficulties in manufacturing and in adjusting bell sound volumeO
In accordance with one aspect o~ the invention there is provided a gong striking mechanism comprising a driving electric motor, including a motor shaft, mounted on a frame within a gong; conversion means rotatably connected to the motor shaft for conve~ting continuous rotational motion of the motor shaft to reciprocal gong striking motion, said conversion means comprising a cylindrical ~l~Z42~
end cam rotatably attached to the motor shaft and a reciprocating rod, one end of which abuts said cylindrical end cam and the other end of which forms a hammer for striking said gong resilient means adapted to absorb impact force during the gong striking motion disposed between said motor and said hammer, said resilient means comprising a spring having one end thereof fixed to said reciprocal rod.
BRIEF DESCRIPTION OF THE DRAWINGS
-In drawings which illustrate embodiments of the invention:
FIGS. 1 and 2 are sectional side and bottom views, ZA~29 respectively, illustrating examples of a conventional motor driven type bell;
FIGS. 3 and 4 are sectional side and bottom views, respectively,.of a first embodiment of the invention;
FIGS. 5 and 6 are sectional side and bottom views, respectively, of a second embodiment of the invention;
FIGS. 7 and 8 are sectional side and bottom views, respectively, of a third embodiment of the invention;
FIGS. 9 and 10 are sectional side and bottom views, respectivelyr of a fourth embodiment of this invention;
FIGS. 11 and 12 are each sectional side views of a fifth embodiment of this invention; and FIGS. 13, 14 and 15 are two sectional side views and a plan view, respectively, of a hammer and a collar between which a resilient means are arranged.
DETAILED DESCRIPTION OF THE INVENTION
In a conventional electric bell as shown in FIG. 1, a pivoting plate 2 is rotatably fixed to a motor shaft 1. A
counter-weight 3 and a striking hammer 4 are attached at opposite ends of plate 2. The striking hammer 4 is arranged in a slot 5 to move foward and backward against a gong 6 during the operation of a motor 7. The location of the striking hammer 4 varies each time it strikes the gong 6 so that the weight balance between the two ends of the pivoting plate 2, with respect to the rotary shaft 1, cannot attain an appropriate balance and fluctuates during the hammer striking motion.
Moreover, when the motor 7 st.arts to rotate and the striking hammer ~ strikes the gong 6`, the rel.atively long plate 2 having counter-weight 3 and the striking hammer 4 at its ends either bends the motor shaft 1 due to the 62~Z~
large torque imparted thereon, or gradually falls off the shaft 1 since there is no provision for fixing the plate 2 to the shaft 1. The latter case occurs when the shaft is relatively small in diameter and it is not possible to insert a pin or the like to fix the shaft 1 and the plate
This invention relates to an electric bell of the type which is driven by a motor and adapted for use in a fire bell, an alarm bell or the like, and more particularly to a gong striking mechanism driven by a motor to strike a gong.
Prior art electric bells have had the drawback of having a rotating pivot plate connected to a motor shaft.
The pivot plate has a counter-weight at one end and a striking hammer at the other. The pivot plate cannot be perfectly balanced and consequently fluctuates during the striking of the gong. As a result, the motor shaft either bends due to the large torque to which it is subjected or the pivot plate falls off the shaft because it cannot properly be secured thereto.
One prior art configuration attempts to overcome this situation, however t it requires complex and expensive parts.
Accordingly, it is an object of this invention to provide a novel gong striking mechanism in which the above-described drawbacks accompanying a conventional electric bell are overcome. Another object of the invention is to provide a mechanism in which reliable and simple parts may be employed to eliminate difficulties in manufacturing and in adjusting bell sound volumeO
In accordance with one aspect o~ the invention there is provided a gong striking mechanism comprising a driving electric motor, including a motor shaft, mounted on a frame within a gong; conversion means rotatably connected to the motor shaft for conve~ting continuous rotational motion of the motor shaft to reciprocal gong striking motion, said conversion means comprising a cylindrical ~l~Z42~
end cam rotatably attached to the motor shaft and a reciprocating rod, one end of which abuts said cylindrical end cam and the other end of which forms a hammer for striking said gong resilient means adapted to absorb impact force during the gong striking motion disposed between said motor and said hammer, said resilient means comprising a spring having one end thereof fixed to said reciprocal rod.
BRIEF DESCRIPTION OF THE DRAWINGS
-In drawings which illustrate embodiments of the invention:
FIGS. 1 and 2 are sectional side and bottom views, ZA~29 respectively, illustrating examples of a conventional motor driven type bell;
FIGS. 3 and 4 are sectional side and bottom views, respectively,.of a first embodiment of the invention;
FIGS. 5 and 6 are sectional side and bottom views, respectively, of a second embodiment of the invention;
FIGS. 7 and 8 are sectional side and bottom views, respectively, of a third embodiment of the invention;
FIGS. 9 and 10 are sectional side and bottom views, respectivelyr of a fourth embodiment of this invention;
FIGS. 11 and 12 are each sectional side views of a fifth embodiment of this invention; and FIGS. 13, 14 and 15 are two sectional side views and a plan view, respectively, of a hammer and a collar between which a resilient means are arranged.
DETAILED DESCRIPTION OF THE INVENTION
In a conventional electric bell as shown in FIG. 1, a pivoting plate 2 is rotatably fixed to a motor shaft 1. A
counter-weight 3 and a striking hammer 4 are attached at opposite ends of plate 2. The striking hammer 4 is arranged in a slot 5 to move foward and backward against a gong 6 during the operation of a motor 7. The location of the striking hammer 4 varies each time it strikes the gong 6 so that the weight balance between the two ends of the pivoting plate 2, with respect to the rotary shaft 1, cannot attain an appropriate balance and fluctuates during the hammer striking motion.
Moreover, when the motor 7 st.arts to rotate and the striking hammer ~ strikes the gong 6`, the rel.atively long plate 2 having counter-weight 3 and the striking hammer 4 at its ends either bends the motor shaft 1 due to the 62~Z~
large torque imparted thereon, or gradually falls off the shaft 1 since there is no provision for fixing the plate 2 to the shaft 1. The latter case occurs when the shaft is relatively small in diameter and it is not possible to insert a pin or the like to fix the shaft 1 and the plate
2. Therefore, the bell of the type described does not have a smooth rotation of the motor 7. Further, the shaft 1 is subjected to a bending force which causes damage thereto In order to overcome these disadvantages, a bell as shown in FIG. 2 has been proposed employing a cam 8 fixedly attached to an axle 9 of a motor 10. A crank rod 11 engages the cam 8 to convert the rotational motion of the motor 10 to a reciprocal motion. This causes a spring plate 12 to reciprocate to strike a gong 13 with a hammer 14 which is attached to the plate 12. The spring plate 12 is fixed at one end to a supporting plate 15 and is connected at the other end to the crank rod 11.
In this bell, however, there exists some problems such as a plurality of assembly processes to be accomplished, high cost, and difficulty in adjustment to obtain an optimum sound volume.
A first embodiment of the invention is shown in FIGS.
In this bell, however, there exists some problems such as a plurality of assembly processes to be accomplished, high cost, and difficulty in adjustment to obtain an optimum sound volume.
A first embodiment of the invention is shown in FIGS.
3 and 4 having a gong 30. The gong 30 is made of iron in the form of a cup or the like.
A mounting plate 31 fixed to the central portion of the inner wall of the gong 30 by an appropriate means, such as a bolt or nut, supports a front wall 32, an intermediate wall 33, and a rear wall 34. Each wall extends downwardly from the mounting plate 31. These three walls 32, 33 and 34 may be made integrally from a i24~9 single steel sheet by bending it suitably to accommodate a bell striking mechanism. A motor 35 is fixedly installed on the rear wall 34. A motor shaft is rotatably inserted through an opening formed in the center of the wall 34. A
cylindrical end cam 36 is rotatably fixed to the sha~t of the motor 35. The end surface of the cam 36 engages with a cylindrical cam follower 37 which rotates and reciprocates through a hole formed in the intermediate wall 33. A groove is formed on the surface of the cam follower in axial alignment therewith. The groove incorporates an elongated pin 3~ adapted to fit in a recess formed in the intermediate wall 33 so that the cam follower 37 is constrained in movement to an opera-ting range. At the opposite side to the end surface of the cam follower 37 which engages the end cam 36, there is a rod portion having a smaller diameter and a hammer 39 at its extremity. The hammer 39 is disposed in proximity with the inner surface of the gong 30. A spring 40 is arranged between the inside of the front wall 32 and the end portion of the cam follower 37, to absorb the impact force exerted on the cam follower 37.
A second embodiment of the invention will be described with reference to FIGS. 5 and 6 and has a gong 30 of the same type as described in the first embodiment. It should be understood that like parts are indicated by like reference numerals in FIGS. 3, 4, 5 and 6. The difference between the first and second embodiment lies in that the latter is mainly composed of a cylindrical cam 36 and a cam follower 37, having at a predetermined position, a protrusion 41 around the periphery thereof. The cam follower 37 has at one end a hammer 39 and abuts directly 1~6Z~
with the end surface of the cam 36 at the other end.
Thus, the elements making up the cam follower body in the first embodiment are eliminated. The only difference in operation resides in that the stroke of the hammer 39 is shorter compared with the first embodiment.
A third embodiment of the invention is shown in FIGS.
7 and 8 in which a supporting plate 70 is fixedly attached to the gong 71 at a central portion thereof. The plate supports a motor 72 and bearings 73. One end of a flexible wire or tube 74 is connected to the shaft of motor 72. The other end is rotatably supported by the two bearings 73.
An eccentric cam 75 is fixed to the flexible wire 74 between the two bearings 73. The cam 75 is located adjacent a pro~rusion 76 formed on the inner surface of the gong wall.
FIGS. 9 and 10 illustrate a fourth embodiment of the invention having a gong 90. There is provided a motor 91, a cam 92 fixed to the motor shaft, a spring plate 93 disposed to engage with the cam, and a hammer 94 fixed to the spring plate. The plate 93 is fixed at one end to the supporting plate 95 so that the hammer 94 faces a protrusion 95 formed on the inner surface of the gong wall. The hammer 94 strikes the protrusion 95.
FIGS. 11, 12, 13, 14 and 15 illustrate a fifth embodiment of the invention having a gong 101. A
supporting plate 106 is fixedly connected to the gong 101~ The plate receives, at one end, a motor 105 connected to a shaft 104. A collar 103 is fixedly attached to shaft 104 in such a manner that it is offset from the center of the collar 103. A hammer 102 having a h()ll~su) ~cylindrical shape, surrounding collar 103 thereby strikes a protrusion 107 once every rotation of the motor shaft.
The hammer maintains a predetermined distance and is restrained around the collar 103 by a rim integrally made at the top edge thereofO In the space between the collar 103 and the hammer 102, there is provided resilient means which absorb, in part, shock resulting from a striking motion of the hammer 102 against the protrusion 107. The resilient means are exemplified in FIGS. 13, 14 and 15 in such a manner that the hammer 102 and the collar 103 are supported resiliently on each other by springs 108 which are fixed at both ends to the grooves formed either in the hammer 102 or the collar 103 (FIG. 13). The hammer 102 and the collar 103 can be resiliently associated with each other by springs 109 which are fixed at one end thereof to the groove formed in the collar 103 and which are free at their other ends (FIG. 14). The hammer 102 and the collar 103 can be resiliently associated with each other by employing a shock absorber such as a spring wire 110 or a plate spring which is fixed around the collar surface by an appropriate fixing means such as a bonding agent (FIG.
15).
Upon energization of the motor, its shaft rotates so that the cylindrical cam 36, the flexible tube 74, the eccentric cam 92 or the collar 102 rotatesO This ca~ses the hammer 39, the eccentric cam 75, the hammer 94 or the hammer 102 to move reciprocally, relative to the gong 30 or the protrusions 76, 95, 107 in order to generate bell sounds. Each time the hammer 39~ the eccentric cam 75, the hammer 94 or the hammer 102 strikes the gong 30 or the protrusions 76, 95, 107, impact forces are exerted upon ~6;~429 the hammer 39, the eccentric cam 75, the hammer 94 or the hammer 102. Impact forces are absorbed in part in the resilient means thereby to cause no damage to the motor shaft by eliminating the possible bending force applied to the shaft.
As is described above, it is a feature of the invention to provide a bell striking mechanism in which driving power for a hammer to strike a gong is supplied from a motor by a converison means rotatably connected directly or indirectly to the motor shaft. The conversion means in one embodiment of the invention preferably comprises a cylindrical end cam rotatably attached to the motor shaft, and cylindrical cam follower on one end of which the end surface of the cam abuts and to the other end of which a reciprocal rod having at the end portion thereof a hammer to strike the gong is fixedly connected.
It is another feature of the invention to provide a bell striking mechanism in which a resilient means is disposed between the motor and a hammer so that impact forces imparted on the hammer during a bell striking motion are absorbed to some extent, thereby causing no damage to the motor shaft.
A mounting plate 31 fixed to the central portion of the inner wall of the gong 30 by an appropriate means, such as a bolt or nut, supports a front wall 32, an intermediate wall 33, and a rear wall 34. Each wall extends downwardly from the mounting plate 31. These three walls 32, 33 and 34 may be made integrally from a i24~9 single steel sheet by bending it suitably to accommodate a bell striking mechanism. A motor 35 is fixedly installed on the rear wall 34. A motor shaft is rotatably inserted through an opening formed in the center of the wall 34. A
cylindrical end cam 36 is rotatably fixed to the sha~t of the motor 35. The end surface of the cam 36 engages with a cylindrical cam follower 37 which rotates and reciprocates through a hole formed in the intermediate wall 33. A groove is formed on the surface of the cam follower in axial alignment therewith. The groove incorporates an elongated pin 3~ adapted to fit in a recess formed in the intermediate wall 33 so that the cam follower 37 is constrained in movement to an opera-ting range. At the opposite side to the end surface of the cam follower 37 which engages the end cam 36, there is a rod portion having a smaller diameter and a hammer 39 at its extremity. The hammer 39 is disposed in proximity with the inner surface of the gong 30. A spring 40 is arranged between the inside of the front wall 32 and the end portion of the cam follower 37, to absorb the impact force exerted on the cam follower 37.
A second embodiment of the invention will be described with reference to FIGS. 5 and 6 and has a gong 30 of the same type as described in the first embodiment. It should be understood that like parts are indicated by like reference numerals in FIGS. 3, 4, 5 and 6. The difference between the first and second embodiment lies in that the latter is mainly composed of a cylindrical cam 36 and a cam follower 37, having at a predetermined position, a protrusion 41 around the periphery thereof. The cam follower 37 has at one end a hammer 39 and abuts directly 1~6Z~
with the end surface of the cam 36 at the other end.
Thus, the elements making up the cam follower body in the first embodiment are eliminated. The only difference in operation resides in that the stroke of the hammer 39 is shorter compared with the first embodiment.
A third embodiment of the invention is shown in FIGS.
7 and 8 in which a supporting plate 70 is fixedly attached to the gong 71 at a central portion thereof. The plate supports a motor 72 and bearings 73. One end of a flexible wire or tube 74 is connected to the shaft of motor 72. The other end is rotatably supported by the two bearings 73.
An eccentric cam 75 is fixed to the flexible wire 74 between the two bearings 73. The cam 75 is located adjacent a pro~rusion 76 formed on the inner surface of the gong wall.
FIGS. 9 and 10 illustrate a fourth embodiment of the invention having a gong 90. There is provided a motor 91, a cam 92 fixed to the motor shaft, a spring plate 93 disposed to engage with the cam, and a hammer 94 fixed to the spring plate. The plate 93 is fixed at one end to the supporting plate 95 so that the hammer 94 faces a protrusion 95 formed on the inner surface of the gong wall. The hammer 94 strikes the protrusion 95.
FIGS. 11, 12, 13, 14 and 15 illustrate a fifth embodiment of the invention having a gong 101. A
supporting plate 106 is fixedly connected to the gong 101~ The plate receives, at one end, a motor 105 connected to a shaft 104. A collar 103 is fixedly attached to shaft 104 in such a manner that it is offset from the center of the collar 103. A hammer 102 having a h()ll~su) ~cylindrical shape, surrounding collar 103 thereby strikes a protrusion 107 once every rotation of the motor shaft.
The hammer maintains a predetermined distance and is restrained around the collar 103 by a rim integrally made at the top edge thereofO In the space between the collar 103 and the hammer 102, there is provided resilient means which absorb, in part, shock resulting from a striking motion of the hammer 102 against the protrusion 107. The resilient means are exemplified in FIGS. 13, 14 and 15 in such a manner that the hammer 102 and the collar 103 are supported resiliently on each other by springs 108 which are fixed at both ends to the grooves formed either in the hammer 102 or the collar 103 (FIG. 13). The hammer 102 and the collar 103 can be resiliently associated with each other by springs 109 which are fixed at one end thereof to the groove formed in the collar 103 and which are free at their other ends (FIG. 14). The hammer 102 and the collar 103 can be resiliently associated with each other by employing a shock absorber such as a spring wire 110 or a plate spring which is fixed around the collar surface by an appropriate fixing means such as a bonding agent (FIG.
15).
Upon energization of the motor, its shaft rotates so that the cylindrical cam 36, the flexible tube 74, the eccentric cam 92 or the collar 102 rotatesO This ca~ses the hammer 39, the eccentric cam 75, the hammer 94 or the hammer 102 to move reciprocally, relative to the gong 30 or the protrusions 76, 95, 107 in order to generate bell sounds. Each time the hammer 39~ the eccentric cam 75, the hammer 94 or the hammer 102 strikes the gong 30 or the protrusions 76, 95, 107, impact forces are exerted upon ~6;~429 the hammer 39, the eccentric cam 75, the hammer 94 or the hammer 102. Impact forces are absorbed in part in the resilient means thereby to cause no damage to the motor shaft by eliminating the possible bending force applied to the shaft.
As is described above, it is a feature of the invention to provide a bell striking mechanism in which driving power for a hammer to strike a gong is supplied from a motor by a converison means rotatably connected directly or indirectly to the motor shaft. The conversion means in one embodiment of the invention preferably comprises a cylindrical end cam rotatably attached to the motor shaft, and cylindrical cam follower on one end of which the end surface of the cam abuts and to the other end of which a reciprocal rod having at the end portion thereof a hammer to strike the gong is fixedly connected.
It is another feature of the invention to provide a bell striking mechanism in which a resilient means is disposed between the motor and a hammer so that impact forces imparted on the hammer during a bell striking motion are absorbed to some extent, thereby causing no damage to the motor shaft.
Claims (2)
1. A gong striking mechanism comprising:
a driving electric motor, including a motor shaft, mounted on a frame within a gong;
conversion means rotatably connected to the motor shaft for converting continuous rotational motion of the motor shaft to reciprocal gong striking motion, said conversion means comprising:
a cylindrical end cam rotatably attached to the motor shaft and a reciprocating rod, one end of which abuts said cylindrical end cam and the other end of which forms a hammer for striking said gong, resilient means adapted to absorb impact force during the gong striking motion disposed between said motor and said hammer, said resilient means comprising a spring having one end thereof fixed to said reciprocal rod.
a driving electric motor, including a motor shaft, mounted on a frame within a gong;
conversion means rotatably connected to the motor shaft for converting continuous rotational motion of the motor shaft to reciprocal gong striking motion, said conversion means comprising:
a cylindrical end cam rotatably attached to the motor shaft and a reciprocating rod, one end of which abuts said cylindrical end cam and the other end of which forms a hammer for striking said gong, resilient means adapted to absorb impact force during the gong striking motion disposed between said motor and said hammer, said resilient means comprising a spring having one end thereof fixed to said reciprocal rod.
2. The gong striking mechansim of claim 1 wherein said conversion means further comprises a cylindrical cam follower located between said cylindrical end cam and said reciprocating rod, said cam follower having a first end abutting said cam and a second end having the reciprocating rod connected thereto, and wherein said resilient means includes a spring fixed to said second end of said cam follower.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000368325A CA1162429A (en) | 1981-01-12 | 1981-01-12 | Gong striking mechanism |
| CA000437278A CA1173673A (en) | 1981-01-12 | 1983-09-21 | Gong striking mechanism |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000368325A CA1162429A (en) | 1981-01-12 | 1981-01-12 | Gong striking mechanism |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000437278A Division CA1173673A (en) | 1981-01-12 | 1983-09-21 | Gong striking mechanism |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1162429A true CA1162429A (en) | 1984-02-21 |
Family
ID=4118894
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000368325A Expired CA1162429A (en) | 1981-01-12 | 1981-01-12 | Gong striking mechanism |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1162429A (en) |
-
1981
- 1981-01-12 CA CA000368325A patent/CA1162429A/en not_active Expired
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |