US3564917A

US3564917A - Maximum air speed indicator

Info

Publication number: US3564917A
Application number: US747569A
Authority: US
Inventors: John E Cronin; Warren H Anderson
Original assignee: TRIMEN Inc
Current assignee: TRIMEN Inc
Priority date: 1968-07-25
Filing date: 1968-07-25
Publication date: 1971-02-23
Anticipated expiration: 1988-02-23

Abstract

SPEEDOMETER COMPRISES CASE HAVING ARCUATE AIR PASSAGEWAY AND INNER CHAMBER WITH SLOT BETWEEN PASSAGEWAY AND CHAMBER, AIR OPENINGS ON CASE COMMUNICATE WITH PASSAGEWAY. PADDLE ASSEMBLY IN CASE INCLUDES PADDLE BLADE IN PASSAGEWAY, ARM CONNECTED TO PADDLE BLADE EXTENDING THEREFROM THROUGH SLOT TO PIVOTAL CONNECTION IN CHAMBER, AND INDICATOR NEEDLE CONNECTED FOR MOVEMENT WITH ARM PADDLE BLADE. BIASING DEVICE URGES PADDLE ASSEMBLY IN DIRECTION OPPOSITE TO DIRECTION OF AIR FLOW THROUGH PASSAGEWAY RATCHET MECHANISM INCLUDES TEETH CONNECTED FOR MOVEMENT WITH PADDLE ASSEMBLY AND PAWL IN RELEASABLE ENGAGEMENT WITH TEETH ARRANGED TO HOLD PADDLE ASSEMBLY AT POINT OF MAXIMUM SWING WHEN AIR FLOWING THROUGH PASSAGEWAY SWINGS PADDLE BLADE AGAINST FORCE OF BIASING DEVICE.

Description

MAXIMUM AIR SPEED INDICATOR Filed July 25, 1968 l Q2. a 56 y W i l '203% l@ Z2 20 lj l United States Patent O 3,564,917 MAXIMUM AIR SPEED INDICATOR John E. Cronin and Warren H. Anderson, Newark, Del., assignors to Trimen Inc., a corporation of Delaware Filed July 2S, 1968, Ser. No. 747,569 Int. Cl. G01f 1 06 U.S. Cl. 73-228 2 Claims ABSTRACT OF THE DISCLOSURE Speedometer comprises case having arcuate air passageway and inner chamber with slot between passageway and chamber. Air openings on case communicate with passageway. Paddle assembly in case includes paddle blade in passageway, arm connected to paddle blade extending therefrom through slot to pivotal connection in chamber, and indicator needle connected for movement with arm paddle blade. Biasing device urges paddle assembly in direction opposite to direction of air flow through passageway. Ratchet mechanism includes teeth connected for movement with paddle assembly and pawl in releasable engagement with teeth arranged to hold paddle assembly at point of maximu-m swing when air flowing through passageway swings paddle blade against force of biasing device.

BACKGROUND OF THE INVENTION The present invention relates to a speed indicating device, and more particularly to a speedometer for skiers.

Prior to the present invention numerous devices have been proposed for measuring speed. Many of these devices such as the type disclosed in Cramer Pat. 2,793,528, granted May 28, 1957, utilize a paddle or vane and the force of air acting thereon to determine the speed of the device relative to the velocity of the air owing around it. However, for the most part, the prior art devices are characterized by their complex modes of operation as well as the numerous components required to construct them.

Accordingly, it is an object of the present invention to provide a speedometer having relatively few parts which operates in a highly successful and trouble-free manner.

SUMMARY OF THE INVENTION In accordance with the present invention a speedometer comprises a case having an arcuate air passageway therein and an inner chamber. A slot is provided between the passageway and the chamber as well as air inlet and outlet openings on the case that communicate with the passageway. A paddle assembly in the case includes a paddle blade in the passageway, an arm connected to the paddle blade extending therefrom through the slot to a pivotal connection in the chamber, and an indicator needle connected for movement with the arm and the paddle blade. A biasing device urges the paddle assembly in a direction opposite to the direction of air flow through the passageway. A ratchet mechanism has teeth connected for movement with the paddle assembly and a pawl in releasable engagement with the teeth is arranged to hold the paddle assembly at its point of maximum swing when air owing through the passageway swings the paddle blade against the force of the biasing device.

The speedometer case may include top and bottom surfaces with an upwardly extending wall between the surfaces. Moreover, the air inlet and outlet openings may be disposed in the upstanding wall of the case. The passageway may extend approximately 180 and the air outlet openings may include an arcuate opening that extends approximately 90.

The pivotal connection of the paddle assembly comprises a rotatable post having a head portion that extends through the case. The biasing device is connected between Cil ice

the post and the paddle assembly so that selected rotation of the post adjusts the force of the biasing device acting on the paddle assembly. The biasing device can be a torsion spring wrapped around the post with one end of the spring engaging the post and the other end connected to the paddle assembly.

Additionally, the paddle assembly may include a counterweight connected to the arm on the side of the pivotal connection opposite the paddle blade. Also, the speedometer case may include an arcuate indicia-carrying panel adjacent the swing of the indicator needle for correlating the position of the needle with speed. The speedometer case may further include straps connected thereto for securing the speedometer in the position of its intended use.

BRIEF DESCRIPTION OF THE DRAWING Novel features and advantages of the present invention will become apparent to one skilled in the art from a reading of the following detailed description in conjunction with the accompanying drawing wherein similar reference characters refer to similar parts and in which:

FIG. 1 is a pictorial view of a skier wearing a speedometer according to the present invention;

FIG. 2 is a front elevational view of a speedometer according to the present invention;

FIG. 3 is a top plan view of the speedometer shown in FIG. 2;

FIG. 4 is a left side elevational View of the speedometer shown in FIGS. 2 and 3;

FIG. 5 is a right side elevational view of the speedometer shown in FIGS. 2 and 3;

FIG. 6 is a sectional view taken along line 66 of FIG. 2; and

FIG. 7 is a sectional View taken along line 7-7 of FIG. 3.

DETAILED DESCRIPTION OF THE INVENTION Referring in more particularity to the drawing, FIG. l illustrates a skier 10 wearing a speedometer 12 according to the present invention. The speedometer is releasably secured to the body of the skier, such as the forearm, for example, and functions in the manner described below to indicate the speed of the skier during his descent. The speedometer 12 comprises a case 14 with a lower part 16 and an upper part 18. The lower part has a bottom surface and an upstanding front wall 22 while the upper part 18 has a top surface 24 with a downwardly extending side wall 26. The upper and lower parts of the case 14 are maintained in assembled relationship by pins 28 on one part that frictionally engage holes 30 on the other part.

As shown best in FIG. 6, an arcuate air passageway 32 is provided inside the case. The passageway is formed in part by the side wall 26 and an inner wall 34 formed by

arcuate wall segments

36, 38 on the upper and lower parts of the case 14. The

arcuate wall segments

36, 38 are spaced from one another so that a slotted opening 40 is defined between them. The case 14 also has an inner chamber 42 which communicates with the arcuate air passageway 32 through the slotted opening 40. An air inlet 44 is provided in the front Wall 22 of the speedometer case. Air outlets are also provided in the case at the end of the arcuate air passageway opposite air inlet 44. One of the air outlets comprises a rectangular shaped opening '46 in the side wall 26 of the case while the other outlet comprises a slotted opening 48 in the side Wall which opening extends approximately 90. As explained more fully below, the air outlets function to relieve back pressure within the arcuate air passageway 32 during operation of the speedometer.

A paddle assembly 50 is located inside the speedometer case 14 for measuring and indicating the speed of the person using the speedometer 12. The assembly comprises a paddle blade 52 located inside the arcuate air passageway 32. An arm 54 connected to the paddle blade 2 extends from the blade through the slotted opening 40 formed by the

arcuate wall segments

36, 38 to a pivotal connection in the chamber 42. The pivotal connection comprises a rotatable post 56 having a head portion 58 that extends through an opening in the top surface 24 of the upper case part 18. The base of the post is frictionally maintained within a recess in the bottom surface of the case and operates in a manner explained more fully below. For the purpose of pivotally attaching the arm 54 inside the chamber 42, the post 56 loosely extends through an opening in the arm at the end of the arm opposite the paddle blade. The arm and paddle blade are thus free to rotate about the post. The arm 54 also carries a counterweight 60 on the side of the post opposite the paddle blade 52. The counterweight serves to offset the weight of the paddle blade so that the arm and paddle blade are balanced on the post.

The paddle assembly 50` also includes an indicator needle 62 connected to the arm 54 for movement therewith. The needle has a pointer portion 64 connected to a circular base 66. The base has a central opening through which the post S6 passes. The underside of the base carries a pair of lugs 68 that enter openings 70 in the arm 54 to position and anchor the indicator needle with respect to the arm 54 and the paddle blade. Accordingly, as the paddle blade and arm move the indicator needle moves with them. The pointer portion 64 of the indicator needle 62 is located adjacent an arcuate indicia-carrying panel or speed scale 72 comprising numbers printed or embossed on the top surface 24 of the upper case part 14 with the numbers of the scale arranged to accurately indicate speed. The pointer portion 64 is visible throughout its full swing through an arcuate window 73 in the case part 14.

A biasing device in the form of a torsion spring 74 urges the paddle assembly 50 in a direction opposite to the direction of air flow through the arcuate passageway 32. The torsion spring 74 is wrapped around the post in the space between the indicator needle 62 and the top surface 24 of the speedometer case 14. One end of the spring is secured to the post and the other end is anchored to the circular base 66 of the indicator needle. Thus, as can readily be understood, rotation of the post 56 through manipulation of the head 58 varies the tension of the torsion spring. With the torsion spring oriented as best shown in FIG. 7 rotation of the post in a counterclockwise direction increases the force the spring exerts upon the paddle assembly in a direction opposite to the direction of air flow through the passageway 3'2. Thus, the speedometer 12 is readily adjusted or calibrated by increasing or decreasing the tension of the spring 74. With a Calibrating source of constant velocity of 40 mph., for example, one can set the tension of the torsion spring so that the paddle blade 52 swings the indicator needle 62 to the number 40 on the indicia-carrying panel 72.

The speedometer 12 of the present invention also includes a ratchet mechanism for holding the paddle assembly at its point of maximum swing whereby the maximum speed of the skier during his descent is registered. The ratchet mechanism includes teeth 76 that extend over a portion of the circumference of the circular base 66 of the indicator needle 62. The ratchet mechanism further includes a pawl 78 in releasable engagement with the teeth 76 on the circular base of the indicator needle. The pawl is rotatably mounted on the upper end of a stationary post 80 connected to the bottom surface of the speedometer case 14. Movement of the pawl in an upward direction is prevented by a downwardly extending projection 82 on the top surface of the speedometer case, as best shown in FIG. 7. The pawl 78 is biased into engagement with the teeth 76 of the ratchet mechanism by a torsion spring 84. The spring 84 is secured at one end to the pawl, and at its other end to the bottom surface 20 of the speedometer case. When the pawl 78 is arranged as shown in FIG. 6, the teeth 76 are inclined in a counterclockwise direction. Accordingly, as the paddle assembly moves in a clockwise direction under the influence of air striking the paddle blade S2 the teeth slide past the pawl. However, when the paddle assembly starts to move in a counterclockwise direction under the influence of the torsion spring 74 the pawl engages the teeth to prevent such movement. The pawl also has a handle portion 86 that extends through an opening 88 in the front wall 22 of the speedometer case. The speedometer is reset by moving the handle to the right as viewed in FIGS. 2 and 6. Such movement moves the pawl out of engagement with the teeth whereby the torsion spring 74 is free to return the paddle assembly to its starting position where the pointer portion `64 indicates zero velocity or speed.

In use, the speedometer 12 of the present invention is secured to the body of the skier 10 by a flexible strap 90 threaded through slotted openings 92 on the speedometer case 14. The speedometer is positioned so that the front wall 22 faces the direction of air ow. As can readily be understood, air enters the air inlet 44 in the front wall 22 of the case. The air exerts a force on the paddle blade 52 which causes the blade to move within the arcuate air passageway 32 against the force of the torsion spring 74. The spring 74 is tensioned so that the force of air on the paddle blade is correlated with the relative speed of the skier. The air outlets including the opening 46 and the arcuate slot 48 function to relieve pressure on the back side of the paddle blade 52 during its swinging movement. With these openings the relationship between the force of the torsion spring 74 and the force of the air acting on the paddle blade 52 is maintained throughout the full swing of the paddle blade. As mentioned above, as the paddle blade moves the indicator needle 62 moves with it and the pointer portion 64 indicates the speed of the skier wearing the speedometer. Moreover, as the paddle assembly swings, the teeth of the ratchet mechanism slide past the pawl 78. However, after the blade reaches its point of maximum swing the paddle assembly 50 is prevented from movement in the opposite direction by engagement of the pawl 78 with the teeth 76. Resetting the speedometer to zero conditions is accomplished by moving the pawl out of engagement with the teeth, as explained above.

We claim:

1. A speedometer comprising a case having an arcuate air passageway therein and an inner chamber, a slot between the passageway and the chamber, air inlet and outlet openings in the case communicating with the arcuate passageway, the air outlet opening including an arcuate opening extending some distance along said case and communicating with the passageway, said arcuate opening functioning to progressively relieve pressure on the back side of the paddle blade as it travels along the passageway, a paddle assembly in the case including a paddle blade in the arcuate passageway, an arm connected to the paddle blade extending therefrom through the slot to a pivotal connection in the inner chamber, and an indicator needle connected for movement with the arm and the paddle blade, biasing means urging the paddle assembly in a direction opposite to the direction of air flow through the arcuate passageway, and a ratchet mechanism including teeth connected for movement with the paddle assembly and a pawl in releasable engagement with the teeth arranged to hold the paddle assembly at its point of maximum swing when air flowing through the arcuate passageway swings the paddle blade against the force of the biasing means.

2. A speedometer as in claim 1 wherein the arcuate air passageway extends approximately 180 and the arcuate opening in the case communicating with the arcuate passageway extends approximately (References on following page) References Cited UNITED STATES PATENTS Vaughan 73-228 Davis 73-228 Bull 73-186 Cramer 73-186 Peltola 73228 Pierman et al 73-189 6 123,855 2/ 1872 Ashcroft 73-396 1,533,674 4/1925 Svenson 73-491 RICHARD C. QUEISSER, Primary Examiner 5 M. SMOLLAR, Assistant Examiner