Title:
INTEGRATED DIURNAL TIDE AND TIME CLOCK
United States Patent 3823544
Abstract:
An integrated diurnal tide and time clock is provided which includes dials showing both the time of high and low tide and also hours. It is operable by a means of a single, synchronous clock motor; and the pointers for the two dials are interconnected by a ratio-providing bead chain gear and tensioner that substantially eliminates normal gearing errors. An economical, but accurate, dual clock results.
US Patent References:
Device for indicating the relative movements of the earth, sun, and moon
Dive - February 1924 - 1484174
Tide-indicating mechanism
Haynes - May 1954 - 2677928
TIDE CLOCK
Wood - August 1970 - 3524313
Device for indicating the relative movements of the earth, sun, and moon
Dive - February 1924 - 1484174
Tide-indicating mechanism
Haynes - May 1954 - 2677928
TIDE CLOCK
Wood - August 1970 - 3524313
Application Number:
05/360297
Publication Date:
07/16/1974
Filing Date:
05/14/1973
View Patent Images:
Export Citation:
Assignee:
Mechtronics Corporation (Stamford, CT)
Primary Class:
Other Classes:
968/209
International Classes:
G04B19/26; G04B19/00; G04B19/02; G04B19/26
Field of Search:
58/3,125R,125B,126R,127R
Primary Examiner:
Wilkinson, Richard B.
Assistant Examiner:
Jackmon, Edith Simmons
Attorney, Agent or Firm:
Johnson, Haynes N.
Claims:
I claim
1. An integrated time and diurnal tide clock including:
2. A clock as set forth in claim 1 in which said interconnecting means includes a bead chain gearing having a sheave on said time clock and a sheave on said tide clock, and a bead chain loop passing over said sheaves, said sheaves having teeth interengageable with said bead chain to set said ratios, the ratio of number of teeth on the time clock to the ratio of number of teeth on the tide clock being 57 to 59.
3. A time clock as set forth in claim 2 including a tensioning means positioned between said sheaves to maintain tension on said bead chain.
4. A unitary time and tide clock operable by a single motor, said clock including:
5. A clock as set forth in claim 4 in which said motor is a synchronous motor directly driving said time clock and said speed reducing means includes toothed sheaves associated with said hands and said indicator and said sheaves being interconnected by a bead chain loop.
1. An integrated time and diurnal tide clock including:
2. A clock as set forth in claim 1 in which said interconnecting means includes a bead chain gearing having a sheave on said time clock and a sheave on said tide clock, and a bead chain loop passing over said sheaves, said sheaves having teeth interengageable with said bead chain to set said ratios, the ratio of number of teeth on the time clock to the ratio of number of teeth on the tide clock being 57 to 59.
3. A time clock as set forth in claim 2 including a tensioning means positioned between said sheaves to maintain tension on said bead chain.
4. A unitary time and tide clock operable by a single motor, said clock including:
5. A clock as set forth in claim 4 in which said motor is a synchronous motor directly driving said time clock and said speed reducing means includes toothed sheaves associated with said hands and said indicator and said sheaves being interconnected by a bead chain loop.
Description:
BACKGROUND OF THE INVENTION
As is well known, the tides, in their twice daily cycle of high and low, occur at a later time each day. The delay being, on average, approximately 25 minutes per cycle or 50 minutes per 24 hours double cycle. For example, if the tide were high at 10:00 a.m. on Monday morning, it would again be high approximately 10:25 p.m. that night, and again high at 10:50 a.m. on Tuesday morning.
Clocks have been designed in the past which show the time of high and low tide. However, as far as I know, such clocks have not used a normal synchronous electric motor without complicated gearing to create the necessary time lag. On the other hand, clocks made with motors designed to operate at a speed corresponding to the tide can not also show regular time without substantial additional expense.
SUMMARY OF THE INVENTION
The present invention uses a simplified gearing arrangement which permits an ordinary synchronous motor (commonly used to operate electric clocks) to also operate a tide clock. According, one may have an integrated tide and time clock that is inexpensive and avoids the complexity of prior designs. This is achieved through use of a bead chain loop interconnecting the two clocks and producing the proper ratio of speed of rotation between the time clock and tide clock. The bead chain loop goes about a rotating sheave associated with the hour hand of the time clock, which sheave includes 57 teeth and goes around a rotating sheave associated with the tide clock, which sheave has 59 teeth. Thus, the tide clock moves in a ratio of 57/59 times the speed of the time clock. This, it turns out, makes the time clock accurate to within the insignificant error of about 5 minutes per year.
DETAILED DESCRIPTION OF THE INVENTION
Turning to the drawings, FIG. 1 shows a front elevation of the integrated clock, having a time dial at the top and a tide dial at the bottom. A section is broken away to show interconnection of the two clocks.
FIG. 2 is a section taken on line 2--2 of FIG. 1. The upper portion shows the inside of the time clock, and the lower portion shows the tide clock.
FIG. 3 is a section taken on line 3--3 of FIG. 1 looking upwardly through the central structure of the tide clock.
The clock itself includes a face plate 1, having a time dial or face 2 and a tide dial or face 3, and a rear plate 8. The time dial 2 has the usual minute and hour hands 4 and 5; and the tide dial 3 has a pointer or indicator 6 which rotates between the "high" and "low" positions on the dial.
Front face 1 and the back face 8 may be secured together by any desired means such as the mounted spacers 9.
The time clock includes a synchronous motor 10, electrically operated. This motor is so geared as to operate the hands 4 and 5 of the time clock at the normal speeds. It does, however, have one feature not common to the usual time clock in that it includes a sheave or pulley 12, pivotally mounted between plates 1 and 8, and interconnected to the hour hand, so that it rotates at the same speed as the hour hand. Sheave 12 carries exactly 57 evenly-spaced teeth 16 and carries a bead chain loop 14 with beads of such size as to mesh with teeth 16.
The tide clock includes the face 3 and the pointer 6. Pointer 6 is interconnected to a pivotally mounted sheave 20 (similar to sheave 12) positioned behind face plate 3 and between the front plate 1 and rear plate 8. It rotates at the same speed as pointer 6. Sheave 20 carries exactly 59 teeth 22 and has bead chain 14 passing around it to drive it. Since they are interconnected by bead chain 14, the ratio of the speeds of rotation of time clock sheave 12 and tide clock sheave 20 will be the ratio of 57:59, the tide clock being slower. The two sheaves, interconnected by the bead chain loop, serve as a speed-reducing means so the pointer 6 of the tide clock runs more slowly than the hour hand of the time clock.
A bead-tensioning spring 30 is positioned between the two clocks. The spring is preferably U-shaped and mounted on plate 8 by mounting bracket 32 attached to one end. It may be of any desired material, but a plastic material with sufficient spring in it to gently press bead chain 14 outwardly works satisfactorily. Tensioning spring 30 contacts the bead chain 14 only on one side of its circuit. Thus, chain 14 travels a straight path as it moves upwardly (in the left side of FIG. 1) between sheave 20 and sheave 12, and is spring-pressed outwardly as it moves downwardly (on the right-hand side of FIG. 1). The purpose of spring 30 is to maintain a slight tension on the bead chain so that it makes contact without slippage with teeth 16 and teeth 22 on sheaves 12 and 20, respectively. Otherwise, if there were slippage, inaccuracy would result. In addition, chain 14 may be slipped off spring 30 in order to allow independent movement of the hands on the two-dials for the sake of setting them initially or correcting any error.
In operation, the two clocks are first set properly by loosening the bead chain as mentioned above and adjusting the hands to the proper time and tide positions. The bead chain is then replaced about the tensioning spring 30 and the electric motor operated. The time clock will then maintain accuracy due to the synchronous motor; and the tide clock will maintain an accuracy, mentioned above, within approximately five minutes over the course of the year.
In designing the combined clock, it is, of course, possible to vary the number of high and low tides shown per revolution. For example, one might have the tide indicator on a full day cycle showing two high and two low tides for each full rotation. In such case, the ratio of teeth in the sheaves would have to be changed by a factor of two. Accordingly, a multiple of the 57:59 ratio, other than the multiple of one, would be used .
As is well known, the tides, in their twice daily cycle of high and low, occur at a later time each day. The delay being, on average, approximately 25 minutes per cycle or 50 minutes per 24 hours double cycle. For example, if the tide were high at 10:00 a.m. on Monday morning, it would again be high approximately 10:25 p.m. that night, and again high at 10:50 a.m. on Tuesday morning.
Clocks have been designed in the past which show the time of high and low tide. However, as far as I know, such clocks have not used a normal synchronous electric motor without complicated gearing to create the necessary time lag. On the other hand, clocks made with motors designed to operate at a speed corresponding to the tide can not also show regular time without substantial additional expense.
SUMMARY OF THE INVENTION
The present invention uses a simplified gearing arrangement which permits an ordinary synchronous motor (commonly used to operate electric clocks) to also operate a tide clock. According, one may have an integrated tide and time clock that is inexpensive and avoids the complexity of prior designs. This is achieved through use of a bead chain loop interconnecting the two clocks and producing the proper ratio of speed of rotation between the time clock and tide clock. The bead chain loop goes about a rotating sheave associated with the hour hand of the time clock, which sheave includes 57 teeth and goes around a rotating sheave associated with the tide clock, which sheave has 59 teeth. Thus, the tide clock moves in a ratio of 57/59 times the speed of the time clock. This, it turns out, makes the time clock accurate to within the insignificant error of about 5 minutes per year.
DETAILED DESCRIPTION OF THE INVENTION
Turning to the drawings, FIG. 1 shows a front elevation of the integrated clock, having a time dial at the top and a tide dial at the bottom. A section is broken away to show interconnection of the two clocks.
FIG. 2 is a section taken on line 2--2 of FIG. 1. The upper portion shows the inside of the time clock, and the lower portion shows the tide clock.
FIG. 3 is a section taken on line 3--3 of FIG. 1 looking upwardly through the central structure of the tide clock.
The clock itself includes a face plate 1, having a time dial or face 2 and a tide dial or face 3, and a rear plate 8. The time dial 2 has the usual minute and hour hands 4 and 5; and the tide dial 3 has a pointer or indicator 6 which rotates between the "high" and "low" positions on the dial.
Front face 1 and the back face 8 may be secured together by any desired means such as the mounted spacers 9.
The time clock includes a synchronous motor 10, electrically operated. This motor is so geared as to operate the hands 4 and 5 of the time clock at the normal speeds. It does, however, have one feature not common to the usual time clock in that it includes a sheave or pulley 12, pivotally mounted between plates 1 and 8, and interconnected to the hour hand, so that it rotates at the same speed as the hour hand. Sheave 12 carries exactly 57 evenly-spaced teeth 16 and carries a bead chain loop 14 with beads of such size as to mesh with teeth 16.
The tide clock includes the face 3 and the pointer 6. Pointer 6 is interconnected to a pivotally mounted sheave 20 (similar to sheave 12) positioned behind face plate 3 and between the front plate 1 and rear plate 8. It rotates at the same speed as pointer 6. Sheave 20 carries exactly 59 teeth 22 and has bead chain 14 passing around it to drive it. Since they are interconnected by bead chain 14, the ratio of the speeds of rotation of time clock sheave 12 and tide clock sheave 20 will be the ratio of 57:59, the tide clock being slower. The two sheaves, interconnected by the bead chain loop, serve as a speed-reducing means so the pointer 6 of the tide clock runs more slowly than the hour hand of the time clock.
A bead-tensioning spring 30 is positioned between the two clocks. The spring is preferably U-shaped and mounted on plate 8 by mounting bracket 32 attached to one end. It may be of any desired material, but a plastic material with sufficient spring in it to gently press bead chain 14 outwardly works satisfactorily. Tensioning spring 30 contacts the bead chain 14 only on one side of its circuit. Thus, chain 14 travels a straight path as it moves upwardly (in the left side of FIG. 1) between sheave 20 and sheave 12, and is spring-pressed outwardly as it moves downwardly (on the right-hand side of FIG. 1). The purpose of spring 30 is to maintain a slight tension on the bead chain so that it makes contact without slippage with teeth 16 and teeth 22 on sheaves 12 and 20, respectively. Otherwise, if there were slippage, inaccuracy would result. In addition, chain 14 may be slipped off spring 30 in order to allow independent movement of the hands on the two-dials for the sake of setting them initially or correcting any error.
In operation, the two clocks are first set properly by loosening the bead chain as mentioned above and adjusting the hands to the proper time and tide positions. The bead chain is then replaced about the tensioning spring 30 and the electric motor operated. The time clock will then maintain accuracy due to the synchronous motor; and the tide clock will maintain an accuracy, mentioned above, within approximately five minutes over the course of the year.
In designing the combined clock, it is, of course, possible to vary the number of high and low tides shown per revolution. For example, one might have the tide indicator on a full day cycle showing two high and two low tides for each full rotation. In such case, the ratio of teeth in the sheaves would have to be changed by a factor of two. Accordingly, a multiple of the 57:59 ratio, other than the multiple of one, would be used .