US2063604A - Electric bell - Google Patents

Description

Dec. 8, 1936.

J. A. W. JACOB ET AL ELECTRIC BELL Filed April 3, 1956 2 Sheets--Sheet 1 Dec. s, 1936. J. A, w. JACOB ET AL 2,063,604

ELECTRIC BELL Filed April 3, 1936 2 Sheets-Sheet 2 Maw/0m: 9 J1?. W/af'a y J7 j /fzl' @www Patented Dec. 8, 1936 ELECTRIC BELL Joseph Adelard Willie Jacob and Leonard Bayne Temple, Montreal, Quebec, Canada Application April 3, 1936, Serial No. 72,472

1 Claim. Y (Cl. 74-54) The presentv invention pertainsto a novel bell designed to be operated by an electric motor and adapted for outdoor `uses such as alarms, church bells, school bells, and the like.

`The principal` object of the invention is to provide asimple, inexpensive and effective device of this character which is positive in operation and produces a clear sound.

The bell member is struck by a pivoted hammer operated by a trip mechanism driven by an electric motor. The trip mechanism swings the hammer out of contact with the bell member, at the same time tensioning a spring acting on the hammer, and when the trip occurs the spring tension causes the hammer to strike. The trip action includes a pin operating in a slot for swinging and releasing the hammer, and in connection therewith, there is provided retaining cam mechanism for positioning the slot to receive the pin.

The clear tone of the bell is produced by a mechanism that instantly breaks contact between the hammer and the bell member after the stroke, inasmuch as a clear tone requires a sharp and instantaneous blow of the hammer on the bell member. This mechanism consists of a spring cushioning device engageable and compressible by the hammer when the latter strikes the bell member. The pressure developed in the device releases the hammer from contact with the bell member instantaneously after the stroke.

The invention is fully disclosed by way of eX- ample in the following description and in the accompanying drawings in which- Figure l is a vertical section of the motor assembly;

Figure 2 is a section on line 2-2 of Figure 1;

Figure 3 is a section on the line 3--3 of Figure 1;

Figure 4 is a side elevation of the bell, partly in section;

Figure 5 is an elevation, partly in section, of the lower part of the mechanism casing;

Figure 6 is a corresponding detail elevation, partly in section, showing the parts in idle position, and

Figure '7 is a similar view showing the parts in tensioned position.

Reference to these views will now be made by use of like characters which are employed to designate corresponding parts throughout.

In Figure, 1 is shown in section a vertical cylinder I which contains the operating motor 2 mounted on a vertical axis. After assembly of the motor, a cap 3 is screwed on the upper end of the cylinder. This cap has a threaded stud 4 for receiving the bell 5 as shown in Figure 4.

A bottom casing or frame-work 6 is secured on the lower end of the cylinder for containing the operating mechanism as will presently be de- 5! scribed. Within this casing. is mounted an upper plate 'I having vertical depending bearing members 8 ywhich in turn join a bottom plate 9 as shown more clearly in Figures l and 5. Another bearing member I0 extends upwardly from the 10 center bottom plate and between the bearings 8 as shown in Figure 1.

In these bearings is journaled a main horizontal shaft having a central groove I2. In this groove is mounted a ball I3 confined to a given position in the central bearing I0 as shown. in Figure 1. The lower end of the motor shaft I4 rests on this ball, the upper end of the shaft being received in the bearing I5 in the cap 3. Beneath this bearing is the armature I6 engaged by suitable brushes Electrical connections are made in any suitable or conventional manner, and the rotor of the motor turns within the eld IB.

The lower end of motor shaft I4 carries a Worm I9 meshing with a worm gear 2|) on a counter- 25 shaft 2| journaled in the bearing I0. This shaft carries a pair of gears 22 meshing with gears 23 on the shaft I I, whereby the latter is driven. At each end of the shaft I I is a cam 24 and a disc 25, the latter carrying a pin 26 for a purpose presently `30 to be described.

Below the shaft II is journaled another horizontal shaft 21 split transversely for purposes of assembly. 'Ihe center of the shaft is grooved or reduced slightly at opposite sides of the vsplit to receive and grip a hammer arm 28. Both sections of the shaft are square near the outer ends as indicated by the numeral 29 in Figures 6 and '7, for the purpose of holding sleeves 30 each having an integral cam 3| directly beneath the pins 26 of the discs 25. A coil spring 32 surrounds each sleeve 36, having one end adjustable against pins 33 on the frame structure or bearing Ill' and the other end fastened to the corresponding cam 3| by a pin 34. Each cam 3| is formed with a notch 35 adapted to receive the corresponding pin 26 to operate the bell as will presently be described in detail.

It will now be apparent that on actuation of the motor, the main shaft is driven through the worm and gear I9, 2D and gears 22, 23. As the discs 25 turn with shaft the pins 26 enter the notches 35 once in each revolution. At this time, the cams 24 engage with cam surface 3| and hold the cams 3| in the position that presents the slots to pins 26, as shown in Figure 6. Immediately afterward, the cams 24 disengage the cams 3| to permit the shaft 29 and hammer arm 28 to be swung by the pins 26 until nally reaching the position shown in Figure 7. During this movement, the springs 32 are Wound or placed under tension, and when the pins 25 pass out of the slots 35, the springs draw the hammer arm 28 into Contact with the bell member 5. The cams 3l then assume the position wherein their concave surfaces 3| are properly disposed for engagement again by the retaining cams 24 that permit entrance of the pins 26 into the slots 35.l

This action will be repeated as long as the motor is running and obviously may be controlled by stopping the motor at the desired time.

In order that the bell have a clear sound, it is necessary tlat the contact between the hammerhead 36 and the bell member 5 be not prolonged. Mechanism for assuring of such action is shown in Figure 4.

A cavity 31 is formed in a solid portion 38 of the central bearing member l0 and slidably supports a horizontal pin 39 bearing against a dog 40 on the pivoted end of the hammer arm 28 above the pivot point. The pin is pressed by a spring 4| towards the dog and is of such strength as to move the hammer-head 42 slightly out of contact with the bell member immediately after the latter has been struck. A long pin 42 is passed through the entire length of the split shaft 21 and headed at both ends 43 (Figure 1) to hold the parts together.

Although a specific embodiment of the invention has been illustrated and described, it will be understood that various alterations in the details of construction may be made without departing from the scope of the invention, as indicated by the appended claim.

What we claim isz- A mechanism of the character described comprising a supporting structure, a main shaft carried thereby, means for rotating said shaft, a second shaft carried by said supporting structure, an arm carried by said second shaft, a slotted member on said second shaft, a disc and pin carried by the first shaft, said pin being adapted to enter said slotted member to turn said second shaft and arm, a spring adapted to be tensioned by the turning of said second shaft by said pin, whereby said spring causes said second shaft and arm to return on removal of said pin from said slotted member, said slotted member having also a cam surface, and a cam carried by the main shaft and *5 engageable with said surface to retain said slotted member'for entry of said pin therein.

J. A. WILLIE JACOB. LEONARD B. TEMPLE.

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