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US4228441A Expired / Lapsed US ⏱️ 0.0 years remaining

Printer head biasing apparatus

Assignee: Helena Laboratories Corp
•
Filing: 1979-02-09
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Granted: 1980-10-14
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Expires: 1999-02-09
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Abstract

Abstract In a chart recorder where a print head is used to record data on a moving strip of chart paper, an improved apparatus for biasing the print head against the moving chart paper. The biasing apparatus provided includes a cantilevered leaf spring to maintain a constant and preset pressure between the print head and the moving chart paper. The distal or fixed end of the leaf spring is anchored to the frame of the chart recorder and the print head is mounted on the free end of the cantilevered leaf spring so that the leaf spring maintains a constant pressure between the print head and the moving chart paper. The cantilevered spring is adjustable to provide the desired amount of pressure between the print head and the moving chart paper. When a new roll of chart paper is inserted into the chart recorder, the cantilever spring re-establishes and maintains the pressure between the print head and the new roll of chart paper.

Inventors

  • 👤 Samuel Rhine

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 00:12
CPC Classifications
G; G01; G01D; G01D15/00; B; B41; B41J; B41J25/00; B41J25/304; B41J25/312

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 162 words
In a chart recorder where a print head is used to record data on a moving strip of chart paper, said chart recorder including a support frame and means for supporting the moving chart paper, said moving chart paper supporting means being spaced apart from said print head to accommodate the moving chart paper therebetween, the improvement comprising: a cantilevered leaf spring having a fixed end provided with an opening and a free end, said fixed end anchored by a retainer means to said support frame; said print head mounted on the free end of said leaf spring adjacent said paper supporting means; said leaf spring for biasing the print head for maintaining constant pressure between the print head and the moving chart paper; said retainer means comprising a plate overlying said fixed end of the leaf spring and having an opening aligned with the opening in said leaf spring; and a threaded fastener extending through said openings into said support frame.
Claim 2
Dependent Claim 162 words
In a chart recorder where a print head is used to record data on a moving strip of chart paper, said chart recorder including a support frame and means for supporting the moving chart paper, said moving chart paper supporting means being spaced apart from said print head to accommodate the moving chart paper therebetween, the improvement comprising: a cantilevered leaf spring having a fixed end provided with an opening and a free end, said fixed end anchored by a retainer means to said support frame; said print head mounted on the free end of said leaf spring adjacent said paper supporting means; said leaf spring for biasing the print head for maintaining constant pressure between the print head and the moving chart paper; said retainer means comprising a plate overlying said fixed end of the leaf spring and having an opening aligned with the opening in said leaf spring; and a threaded fastener extending through said openings into said support frame.
Claim 3
Dependent Claim 24 words
The invention as defined in claim 1 wherein means are provided for adjusting the pressure between the print head and the moving chart paper.
Claim 4
Dependent Claim 47 words
The invention as defined in claim 1 wherein means are provided for adjusting the pressure between the print head and the moving chart paper, said adjusting means flexing said free end of said leaf spring by applying a force adjacent the fixed end of the leaf spring.
Claim 5
Dependent Claim 33 words
The invention as defined in claim 1 wherein said retainer means includes biasing means to adjustably engage the leaf spring to thereby adjust pressure between the print head and the moving chart paper.
Claim 6
Dependent Claim 34 words
The invention as defined in claim 4 wherein said biasing means include one or more threaded elements adjustably carried by said plate, the bottom of each threaded element being engageable with said leaf spring.
Claim 7
Dependent Claim 49 words
The invention as defined in claim 1 wherein said retainer means includes a shim in contact with said leaf spring for flexing said leaf spring to adjust the pressure between said print head and said moving chart paper; said shim having an opening through which said threaded fastener extends.
Claim 8
Dependent Claim 24 words
The invention as defined in claim 6 wherein said shim is located between said support frame and said fixed end of said leaf spring.
Claim 9
Dependent Claim 138 words
In a chart recorder where a print head is used to record data on a moving strip of chart paper, said chart recorder including a support frame and means for supporting the moving chart paper, said moving chart paper supporting means being spaced apart from said print head to accommodate the moving chart paper therebetween, the improvement comprising: a cantilevered leaf spring having a fixed end and a free end, said fixed end anchored by a retainer means to said support frame; said print head mounted on the free end of said leaf spring adjacent said paper supporting means; said leaf spring for biasing the print head for maintaining constant pressure between the print head and the moving chart paper; said retainer means including means to adjust the pressure between said print head and the moving chart paper.
Claim 10
Dependent Claim 138 words
In a chart recorder where a print head is used to record data on a moving strip of chart paper, said chart recorder including a support frame and means for supporting the moving chart paper, said moving chart paper supporting means being spaced apart from said print head to accommodate the moving chart paper therebetween, the improvement comprising: a cantilevered leaf spring having a fixed end and a free end, said fixed end anchored by a retainer means to said support frame; said print head mounted on the free end of said leaf spring adjacent said paper supporting means; said leaf spring for biasing the print head for maintaining constant pressure between the print head and the moving chart paper; said retainer means including means to adjust the pressure between said print head and the moving chart paper.
Claim 11
Dependent Claim 145 words
In a chart recorder where a print head is used to record data on a moving strip of chart paper, said chart recorder including a support frame and means for supporting the moving chart paper, said moving chart paper supporting means being spaced apart from said print head to accommodate the moving chart paper therebetween, the improvement comprising: a cantilevered leaf spring having a fixed end and a free end, said fixed end anchored by a retainer means to said support frame; said print head mounted on the free end of said leaf spring adjacent said paper supporting means; said leaf spring for biasing the print head for maintaining constant pressure between the print head and the moving chart paper; said retainer means including biasing means to adjustably engage the leaf spring to thereby adjust pressure between said print head and the moving chart paper.
Claim 12
Dependent Claim 145 words
In a chart recorder where a print head is used to record data on a moving strip of chart paper, said chart recorder including a support frame and means for supporting the moving chart paper, said moving chart paper supporting means being spaced apart from said print head to accommodate the moving chart paper therebetween, the improvement comprising: a cantilevered leaf spring having a fixed end and a free end, said fixed end anchored by a retainer means to said support frame; said print head mounted on the free end of said leaf spring adjacent said paper supporting means; said leaf spring for biasing the print head for maintaining constant pressure between the print head and the moving chart paper; said retainer means including biasing means to adjustably engage the leaf spring to thereby adjust pressure between said print head and the moving chart paper.
Claim 13
Dependent Claim 150 words
In a chart recorder where a print head is used to record data on a moving strip of chart paper, said chart recorder including a support frame and means for supporting the moving chart paper, said moving chart paper supporting means being spaced apart from said print head to accommodate the moving chart paper therebetween, the improvement comprising: a cantilevered leaf spring having a fixed end and a free end, said fixed end anchored by a retainer means to said support frame; said print head mounted on the free end of said leaf spring adjacent said paper supporting means; said leaf spring for biasing the print head for maintaining constant pressure between the print head and the moving chart paper; said retainer means including a shim in contact with said leaf spring for flexing said leaf spring to adjust the pressure between said print head and the moving chart paper.
Claim 14
Dependent Claim 150 words
In a chart recorder where a print head is used to record data on a moving strip of chart paper, said chart recorder including a support frame and means for supporting the moving chart paper, said moving chart paper supporting means being spaced apart from said print head to accommodate the moving chart paper therebetween, the improvement comprising: a cantilevered leaf spring having a fixed end and a free end, said fixed end anchored by a retainer means to said support frame; said print head mounted on the free end of said leaf spring adjacent said paper supporting means; said leaf spring for biasing the print head for maintaining constant pressure between the print head and the moving chart paper; said retainer means including a shim in contact with said leaf spring for flexing said leaf spring to adjust the pressure between said print head and the moving chart paper.

References Cited (Backward Citations)

US3187332A Cited
US3312980A Cited
US3346871A Cited
US4085407A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-10-14 1984-04-14 1984-10-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-10-14 1988-04-14 1988-10-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-10-14 1992-04-14 1992-10-14 $7700.00 Window Closed / Lapsed

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