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US3989116A Expired / Lapsed US ⏱️ 0.0 years remaining

Battery-powered cart

Assignee: Individual
•
Filing: 1975-05-27
•
Granted: 1976-11-02
•
Expires: 1995-05-27
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Abstract

Abstract A battery-powered cart operatable by a man walking ahead through the medium of a rope attached thereto which is in a forwardly extended state. The rope is connected at the rear end via a sliding member to a spring attached to the cart at a predetermined position in a manner such that the spring urges the rope backwards as it is pulled forwards. The cart incorporates an electric motor, an electromagnetic brake, a battery, and speed-control system electrically connecting with said motor and brake so that the cart moves behind the operator at a speed similar to a man's average walking speed even on a slope, and reduces the speed or comes to a stop as the man slows down or stops because of the slack of the rope.

Inventors

  • 👤 Fujikiyo Hirano

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 09:57
CPC Classifications
B; B62; B62B; B62B5/00; B62B5/0026; A; A63; A63B; A63B55/00; A63B55/60; A63B2055/603; A63B2055/604; B62B2202/00; B62B2202/40; B62B2202/404; B62B5/0069; B62B5/0073; B62B5/06; B62B5/068; Y; Y02; Y02T; Y02T10/00; Y02T10/60; Y02T10/72; Y10; Y10S; Y10S280/00; Y10S280/05

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 503 words
In a cart designed to be pulled by a person, said cart having a longitudinal frame (10), said frame defining front and the rear cart ends, with at least one cart drive shaft (22) at one end, a motor (24) and an electromagnetic brake (25) coupled to said drive shaft (22) supported on said frame, in combination: a. first and second electrically conductive guide rods (27, 26) longitudinally supported on said frame between said ends, said rods having connective leads for connection to a battery (E); b. a sliding member (20) disposed longitudinally for sliding motion along said guide rods (26, 27), first and second slide contacts (N, M) on said sliding member (20), spring means (21) attached to said frame (10) and said sliding member towards said rear end, a rope (18) attached to said sliding member disposed to pull it towards the front end; c. a brake arrangement consisting of at least first and second brake contacts (B 3 , B 2 ) disposed towards said cart rear end longitudinally along said first guide rod (27) for engagement by said first slide contact (N) including a first circuit having first step resistance means (R 2 ) coupled to said brake (25) and said first rod (27), said first slide contact (N) closing said first circuit when touching one of said first and second brake contacts (B 3 , B 2 ), the first of said brake contacts (B 3 ) supplying a greater electromagnetic brake force on said brake (25) via said first step resistance means (R 2 ) than the second brake contact (B 2 ); d. a drive arrangement consisting of at least first and second drive contacts (A 2 , A 1 ) disposed towards said cart front end, longitudinally along said second guide rod (26) for engagement by said second slide contact (M) including a second circuit having second step resistance means (R 1 ) coupled to said motor (24) and said second rod (26), said second slide contact (M) closing said second circuit when touching one of said first and second drive contacts (A 2 , A 1 ), the first of said contacts (A 1 ) supplying a greater amount of power to said motor (24) via said second step resistance means (R 1 ) than the second drive contact (A 2 ), whereby when said rope (18) pulls said sliding member (20) from the rear end towards said front end, said brake (25) decreases as said first slide contact (N) moves forward from said first brake contact (B 3 ) to said second brake contact (B 2 ), so as to lessen the brake effect on said drive shaft, said motor starting up as said second slide contact (M) touches said first drive contact (A 2 ) and the drive speed increasing as said slide contact (M) touches said second drive contact (A 1 ), said actions being reversed as said rope is released and said spring (21) pulls said slide member (20) backwards.
Claim 2
Dependent Claim 503 words
In a cart designed to be pulled by a person, said cart having a longitudinal frame (10), said frame defining front and the rear cart ends, with at least one cart drive shaft (22) at one end, a motor (24) and an electromagnetic brake (25) coupled to said drive shaft (22) supported on said frame, in combination: a. first and second electrically conductive guide rods (27, 26) longitudinally supported on said frame between said ends, said rods having connective leads for connection to a battery (E); b. a sliding member (20) disposed longitudinally for sliding motion along said guide rods (26, 27), first and second slide contacts (N, M) on said sliding member (20), spring means (21) attached to said frame (10) and said sliding member towards said rear end, a rope (18) attached to said sliding member disposed to pull it towards the front end; c. a brake arrangement consisting of at least first and second brake contacts (B 3 , B 2 ) disposed towards said cart rear end longitudinally along said first guide rod (27) for engagement by said first slide contact (N) including a first circuit having first step resistance means (R 2 ) coupled to said brake (25) and said first rod (27), said first slide contact (N) closing said first circuit when touching one of said first and second brake contacts (B 3 , B 2 ), the first of said brake contacts (B 3 ) supplying a greater electromagnetic brake force on said brake (25) via said first step resistance means (R 2 ) than the second brake contact (B 2 ); d. a drive arrangement consisting of at least first and second drive contacts (A 2 , A 1 ) disposed towards said cart front end, longitudinally along said second guide rod (26) for engagement by said second slide contact (M) including a second circuit having second step resistance means (R 1 ) coupled to said motor (24) and said second rod (26), said second slide contact (M) closing said second circuit when touching one of said first and second drive contacts (A 2 , A 1 ), the first of said contacts (A 1 ) supplying a greater amount of power to said motor (24) via said second step resistance means (R 1 ) than the second drive contact (A 2 ), whereby when said rope (18) pulls said sliding member (20) from the rear end towards said front end, said brake (25) decreases as said first slide contact (N) moves forward from said first brake contact (B 3 ) to said second brake contact (B 2 ), so as to lessen the brake effect on said drive shaft, said motor starting up as said second slide contact (M) touches said first drive contact (A 2 ) and the drive speed increasing as said slide contact (M) touches said second drive contact (A 1 ), said actions being reversed as said rope is released and said spring (21) pulls said slide member (20) backwards.

References Cited (Backward Citations)

US2879858A Cited
US3247923A Cited
US3731756A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-11-02 1980-05-03 1980-11-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-11-02 1984-05-03 1984-11-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-11-02 1988-05-03 1988-11-02 $7700.00 Window Closed / Lapsed

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