LABORATORY HOT PLATE

• US 3,766,360 A
• Filed: 08/07/1972
• Issued: 10/16/1973
• Est. Priority Date: 08/07/1972
• Status: Expired due to Term

• Current Assignee: Richard L. Schmitz, Roy T. Eddleman
• Original Assignee: Richard L. Schmitz, Roy T. Eddleman
• Inventors: Eddleman, Roy T., Schmitz, Richard L.
• Primary Examiner(s): Mayewsky, Volodymyr Y.
• Application Number:
  US05/278,527
• Time in Patent Office: 435 Days
• Field of Search: 219/347,353,354,355,415,417,432,433,438,439,441,442,461,521 259/102 99/348,444,445,446
• US Class Current: 219/415
• CPC Class Codes: B01L 7/00 Heating or cooling apparatus autoclaves B01J3/04; Heat insulating devices
• CPC Class Codes: H05B 3/68 Heating arrangements specially adapted for cooking plates or analogous hot-plates

Abstract

A laboratory hot plate useful for heating liquids including a container platform, a curved reflecting surface extending upwardly from the platform, a viewing and spillway trough passing through the reflecting surface and a heating element located inwardly from said reflecting surface whereby the heat emitted from said element is reflected inwardly toward the container platform. The hot plate has the ability to heat liquids at a very fast rate and may be combined with a magnetic stirrer. The trough permits viewing the contents of a transparent container and also provides a spillway in case of container breakage.

Claims

1. A laboratory hot plate useful for heating liquids held in a container comprising:

a base;

a generally horizontal container platform Supported by said base;

a curved reflecting surface extending upwardly from said platform, said surface being in the shape of an inwardly facing concave curve rotated about the vertical axis of said platform;

a viewing and spillway trough having an opening of at least 10* passing through said reflecting surface and having its lower surface at least as low as the surface of said platform;

a longitudinal, curved, radiant electrical heating element mounted in the opening formed by said curved reflecting surface and near the surface thereof, whereby the radiant heat, emitted by said element is reflected inwardly by said surface; and

electrical connection means attached to said heating element and supplying electrical current to said heating element for heating thereof.

2. The hot plate of claim 1 wherein said concave curve is partially semi-circular and has two straight line tangents.

3. The hot plate of claim 1 wherein said concave curve is a parabola.

4. The hot plate of claim 1 wherein the sides of said trough are planar and lie along two planes which intersect at the vertical axis of said platform and are spaced apart less than about 90* and more than about 10*.

5. The hot plate of claim 4 wherein said sides are spaced apart about 40*.

6. The hot plate of claim 1 wherein said reflecting surface is plated with a corrosion resistant, highly reflective material.

7. The hot plate of claim 1 further including magnetic stirrer means located below said platform and attached to said base.

8. A fast heating laboratory hot plate useful for heating a liquid held in a container having a cylindrically shaped lower portion comprising:

a base;

a generally horizontal circular container platform supported by said base;

a curved reflecting surface extending upwardly from said platform, said surface being in the shape of an inwardly facing concave curve rotated about the vertical axis of said platform;

a viewing and spillway trough having an opening of at least 10* passing through said reflecting surface and having its lower surface at least as low as the surface of said platform, said trough having generally vertical sides which are spaced from each other about 40* at the intersection of said platform and said reflecting surface;

a longitudinal semi-circular electrical heating element mounted in the opening formed by said curved reflecting surface and near the surface thereof, whereby the radiant heat emitted by said element is reflected inwardly by said surface; and

electrical connection means attached to said heating element and supplying electrical current to said heating element for heating thereof.

9. The hot plate of claim 8 wherein the diameter of said circular platform and the upper opening of said reflecting surface are about equal.

10. The hot plate of claim 9 wherein said diameter is about 2.8 inches and the electrical heating element has a rating of about 500 watts.