US3377742A

US3377742A - Transmission for slot racers

Info

Publication number: US3377742A
Application number: US527332A
Authority: US
Inventors: Sheldon Philip; Thomas J Bacsanyi
Original assignee: MODEL PRODUCTS CORP
Current assignee: Kenner Parker Toys Inc; MODEL PRODUCTS CORP
Priority date: 1966-02-14
Filing date: 1966-02-14
Publication date: 1968-04-16
Anticipated expiration: 1985-04-16

Description

A ril 16, 1968 P. SHELDON ETAL 3,377,742

TRANSMISSION FOR SLOT RACERS 7 Filed Feb. '14. 1966 lllllllllllllll l nvmvroas PHILIP SHELDONI BY THOMAS J. BACSANYI WNVMW/ ATTORNEYS United States Patent 3,377,742 TRANSMISSION FOR SLOT RACERS Philip Sheldon, Rochester, and Thomas J. Bacsanyi,

Livonia, Mich., assignors to Model Products Corporation, Mount Clemens, Mich., a corporation of Michigan Filed Feb. 14, 1966, Ser. No. 527,332

6 Claims. (Cl. 46-243) This invention relates to a new and improved drive train for a toy slot type racing car and has particular reference to an automatic two speed transmission for use in a slot racer.

In conventional slot type racing cars the electric drive motor is geared directly to the drive axle. The gear ratio is usually selected as a compromise between a gear ratio which would allow the racer to attain high track speeds, and one which would provide rapid starting and acceleration of the racer. The invention provides a reliable yet inexpensive two speed transmission for a slot type racing car which includes a low speed drive having a relatively high gear ratio to permit rapid starting and acceleration of the racer and a high speed drive having a low gear ratio for high track speed operation. The transmission shifts automatically from the low speed drive to the high speed drive and back again in order to assure maximum performance as the racer is driven around the race track.

An object of the invention is to provide an improved transmission for a toy racing car.

Another object of the invention is to provide an automatic two speed transmission for a slot racer.

Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawings illustrating a preferred embodiment of the invention, wherein:

FIGURE 1 is a top view of a slot racer according to the invention with part of the chassis broken away;

FIGURE 2 is an enlarged view showing the drive train with the automatic transmission in the low speed position;

FIGURE 3 is like FIGURE 2 but shows the transmission in the high speed position;

FIGURE 4 is a sectional view taken along line 4-4 of FIGURE 2; and

FIGURE 5 is a sectional view taken along line 5-5 of FIGURE 4.

A toy racing car according to the invention includes an elongated chassis having a front axle 12 journaled in front bearings 14 carried by the chassis. Front wheels 16 are secured on the ends of the front axle 12. Rear drive wheels 18 are secured to a rear axle 20 rotatably mounted on the chassis 10. The

wheels

16 and 18 support the racer on a conventional slot type track 22 over a guide slot 24 having electrified power rails 26 at either side thereof. A conventional contact and guide member 28 is mounted in the front of the chassis 10. Electric drive motor 30 is secured to the chassis adjacent the rear axle 20 with the drive shaft thereof oriented parallel to the rear axle. Lead-in wires 32 are secured to the contacts carried by contact member 28 and supply electric power to the motor 30 from the rails 26.

Motor drive shaft 34 is journaled in bearings 36 carried by chassis 10 and extends outwardly to each side thereof. Low speed gear 38 and high speed gear 40 are secured to the ends of the drive shaft 34 outside of the chassis 10. Low speed gear 42 is journaled in a bearing 44 carried on one side of the chassis 10 and high speed gear 46 is journaled in a bearing 48 carried by the chassis opposite bearing 44. The drive axle 20 is journaled in

axial bores

50 and 52 in the low speed and

high speed gears

42 and 46, respectively. The

gears

42 and 46 are provided with hubs 53 which are journaled in

bearings

44 and 48 and 'ice have end faces provided with a plurality of pin engaging slots 54. Gear 38 engages low gear 42 and gear 40 engages gear 46 so that the motor 30 rotates the

gears

42 and 46 at all times. The gear ratios are such that the gear 42 is rotated at a lower speed than the gear 46.

Collar 56 is secured to the drive axle 20 adjacent gear 46 by set screw 58. A collar 60 is slidably mounted on axle 20 adjacent gear 42.

Control links

62 and 64 connect the

collars

56 and 60 by means of pivot joints which allow the links to move radially outwardly from the slow speed position as shown in FIGURE 2 to the high speed position shown in FIGURE 3. Links 62 carry weights 66 adjacent their connection with links 64. Shift pin 68 is secured to the free collar 60 by a set screw and projects toward the low speed gear 42 so as to engage one of the slots 54 in the hub 53 thereof when the collar 60 is in the low speed position shown in FIGURES 2, 4 and S. Shift pin 70 is also secured to the collar 60 by a set screw and extends toward the slots 54 in the: hub 53 of high speed gear 46. Pin 70 has a sliding fit in bore 73 of fixed collar 56 so that collar 60 rotates with axle 20 and collar 56. Spring 74 is confined between

collars

56 and 60 on pin 70 and serves to bias the collar 60 toward the low speed position of FIGURE 4.

When the racer is started the collar 60) is held adjacent the low speed gear 42 by spring 74 and pin 68 engages one of the slots 54 in low speed gear 42 so that the axle 20 and rear wheels 18 are driven at the same rotational speed as the gear 42. High speed gear 46 is then rotated freely on the axle 20 by the motor 30. As the racer accelerates, the rotating weights 66 are thrown radially outwardly of the drive axle 20 and

links

62 and 64 draw the collar 60 against the action of the spring 74 toward fixed collar 56 until the high speed position illustrated in FIG- URE 3 is reached wherein pin 68 has been moved out of engagement with the slot 54 in the hub of low speed gear 42 and pin 70 has been moved through bore 72 and into engagement with one of the slots 54 in the hub of high speed gear 46. The gear 42 is now rotating freely relative to axle 20 which is driven through the

high speed gears

40 and 46.

When the racer is slowed, the centrifugal force exerted by weights 66 is reduced and the spring 74 moves the collar 60 away from fixed collar 56, and the pin 70 disengages gear 46 while pin 68 engages gear 42 at the appropriate shift speed so that the motor 30 drives the axle 20 through the low speed gear train. The

shift pins

68 and 70 are adjusted relative to collar 60 so that the shift from the low speed to high speed gears and back again occurs smoothly without locking the wheels.

It will be apparent that the pin 68 could be eliminated and the pin 70 extended outwardly from the collar 60 into engagement with one of the slots 54 in the hub of the low speed gear 42 if desired, so that a single pin would perform the function of the two pins shown in the illustrated embodiment of the invention.

While we have illustrated and described a preferred embodiment of our invention, it is understood that this is capable of modification, and we therefore do not wish to be limited to the precise details set forth, but desire to avail ourselves of such changes and alterations as fall within the purview of the following claims.

What we claim as our invention is:

1. A slot type racer having a two-speed automatic transmission comprising a chassis, an axle rotatably supported by said chasssis, a drive wheel mounted on said axle and engageable with a track so as to drive the racer therealong, low and high speed gears journaled on said axle, an electric drive motor carried by said chassis, drive means operatively connecting said motor to said gears so that the motor continuously rotates such gears, and automatic shift means carried by said axle and operable responsive to centrifugal force to connect said low speed gear to said axle at low axle speeds and to connect said high speed gear to said axle at high axle speeds.

2. A toy racer as in claim 1, wherein said automatic shift means comprises a fixed collar on said axle, a free collar slidably mounted on said axle, a pair of links connecting said collars with one end of each link pivotally secured to one of said collars and the other ends thereof pivotally joined to allow radial movement of the links relative to the axle, spring means urging said collars apart, gear shift means carried by said free collar and extending therefrom toward each of said axle gears, said gears each having means thereon engageable by said gear shift means, said gear shift means being arranged so that at low axle speeds said spring holds said collars apart to engage said gear shift means with said low speed gear so that the motor rotates the axle through said low speed gear and fixed collar, and at high axle speeds said links are thrown radially away from said axle "by centrifugal force to move said free collar toward said fixed collar against the force of said spring means to disengage said gear shift means from said low speed gear and engage said gear shift means with said high speed gear so that the motor then drives the axle through said high speed gear and said fixed collar.

3. A racer as in claim 2 wherein said gears are journaled in bearings carried by said chassis and secure said axle relative thereto.

4. A racer as in claim 2 wherein said drive motor is positioned adjacent said axle with the drive shaft oriented parallel thereto, and said drive means comprises gears mounted on the opposite ends of said drive shaft and engaged with said high and low speed gears.

5. A racer as in claim 2 wherein said gear change means includes a pin secured to said free collar and extending slidably through an opening in said fixed collar.

6. A racer as in claim 4 including a drive wheel on each end of said axle and wherein said low and high speed gears are spaced apart and each disposed adjacent one of said wheels, said automatic shift means being mounted on said axle between said gears.

References Cited UNITED STATES PATENTS 12/1964 Ziroli 46243 X 1/1966 Thompson 180-75

Claims

1. A SLOT TYPE RACER HAVING A TWO-SPEED AUTOMATIC TRANSMISSION COMPRISING A CHASSIS, AN AXLE ROTATABLY SUPPORTED BY SAID CHASSIS, A DRIVE WHEEL MOUNTED ON SAID AXLE AND ENGAGEABLE WITH A TRACK SO AS TO DRIVE THE RACER THEREALONG, LOW AND HIGH SPEED GEARS JOURNALED ON SAID AXLE, AN ELECTRIC DRIVE MOTOR CARRIED BY SAID CHASSIS, DRIVE MEANS OPERATIVELY CONNECTING SAID MOTOR TO SAID GEARS SO THAT THE MOTOR CONTINUOUSLY ROTATES SUCH GEARS, AND AUTOMATIC SHIFT MEANS CARRIED BY SAID AXLE AND OPERABLE RE-