Patent US4021036A successfully refreshed from Google Patents.
US4021036A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tennis teaching machine with ball projector
Assignee: Individual
•
Filing: 1975-12-05
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Granted: 1977-05-03
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Expires: 1995-12-05
Abstract
Abstract A tennis teaching machine has a ball hopper slidably mounted on a vertical support. A hollow extension arm protrudes from the ball hopper and has a ball projection mechanism at the end. A rotating ball tray supported within the ball hopper supplies balls to the extension arm and ball projection mechanism. A control unit has a tapedeck which automatically activates the ball projection mechanism when a sensor detects a strip of metal foil on magnetic tape played by a tapedeck. The tennis teaching machine is positioned between two training mats upon which various tennis technique training indicia are inscribed. The student listens to instructions from the control unit and strokes a tennis ball dropped on cue from the extension arm. When stroking the tennis ball, the student positions his feet and racket as indicated by the training indicia on the mats.
Inventors
- 👤 David M. Nelson
- 👤 William Stribrsky
- 👤 John A. Britz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:39
CPC Classifications
A; A63; A63B; A63B69/00; A63B69/38; A63B47/00; A63B47/002
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
82 words
A tennis teaching machine adapted for projecting tennis balls in response to an automatic control comprising: a supporting means; an extension arm connected to said supporting means; ball projection means remote from said supporting means on said extension arm; control means connected to said ball projection means, said control means having a tapedeck for automatic activation of said ball projection means in coordination with recorded tennis technique instructions in which said ball projection means comprises a solenoid for projecting the tennis balls.
Claim 2
Dependent Claim
82 words
A tennis teaching machine adapted for projecting tennis balls in response to an automatic control comprising: a supporting means; an extension arm connected to said supporting means; ball projection means remote from said supporting means on said extension arm; control means connected to said ball projection means, said control means having a tapedeck for automatic activation of said ball projection means in coordination with recorded tennis technique instructions in which said ball projection means comprises a solenoid for projecting the tennis balls.
Claim 3
Dependent Claim
21 words
The machine of claim 1 in which said supporting means comprises a pole on which said ball hopper is slidably engaged.
Claim 4
Dependent Claim
16 words
The machine of claim 1 in which said ball projection means includes springs for ball retension.
Claim 5
Dependent Claim
27 words
The machine of claim 1 in which said tapedeck has a metal foil sensing means mounted thereon for activating said ball projection means at a predetermined time.
Claim 6
Dependent Claim
24 words
The machine of claim 4 in which a manual control connects across said metal foil sensing means for manually activating said ball projection means.
Claim 7
Dependent Claim
125 words
A tennis teaching machine system adapted for automatically bouncing tennis balls within a predefined area on a training mat comprising: (a) a training mat having tennis technique learning indicia inscribed thereon; (b) a supporting pole; (c) ball hopper slidably mounted on said supporting pole; (d) an extension arm connected to said ball hopper; (e) a ball projection means remote from said ball hopper on said extension arm; (f) motor driven rotary ball tray mounted in said ball hopper to supply balls to said extension arm and ball projection means; and (g) control unit electrically connected to said ball projection means, said control unit having a tapedeck with metal foil sensing means for automatically activating said ball projection means in coordination with recorded tennis technique instructions.
Claim 8
Dependent Claim
125 words
A tennis teaching machine system adapted for automatically bouncing tennis balls within a predefined area on a training mat comprising: (a) a training mat having tennis technique learning indicia inscribed thereon; (b) a supporting pole; (c) ball hopper slidably mounted on said supporting pole; (d) an extension arm connected to said ball hopper; (e) a ball projection means remote from said ball hopper on said extension arm; (f) motor driven rotary ball tray mounted in said ball hopper to supply balls to said extension arm and ball projection means; and (g) control unit electrically connected to said ball projection means, said control unit having a tapedeck with metal foil sensing means for automatically activating said ball projection means in coordination with recorded tennis technique instructions.
Claim 9
Dependent Claim
112 words
A tennis teaching machine adapted for projecting tennis balls in response to an automatic control, comprising: a supporting means; an extension arm connected to said supporting means; ball projection means remote from said supporting means on said extension arm; control means connected to said ball projection means, said control means having a tapedeck for automatic activation of said ball projection means in coordination with recorded tennis technique instructions wherein a ball hopper connects with said supporting means and said extension arm and wherein said ball hopper has a motor driven rotary ball tray supported therein and a ball position switch on said extension arm for activating said motor driven rotary ball tray.
Claim 10
Dependent Claim
112 words
A tennis teaching machine adapted for projecting tennis balls in response to an automatic control, comprising: a supporting means; an extension arm connected to said supporting means; ball projection means remote from said supporting means on said extension arm; control means connected to said ball projection means, said control means having a tapedeck for automatic activation of said ball projection means in coordination with recorded tennis technique instructions wherein a ball hopper connects with said supporting means and said extension arm and wherein said ball hopper has a motor driven rotary ball tray supported therein and a ball position switch on said extension arm for activating said motor driven rotary ball tray.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-05-02 | 1980-11-01 | 1981-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-02 | 1984-11-01 | 1985-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-02 | 1988-11-01 | 1989-05-03 | $7700.00 | Window Closed / Lapsed |