Optical operating fluid detector for the optical detection of operating fluid for a hand-guided garden, forestry and/or construction machining appliance, and hand-guided garden, forestry and/or construction machining appliance

Patent metadata

Field	Value
Publication number	US-11940316-B2
Application number	US-202017122459-A
Country	US
Kind code	B2
Filing date	Dec 15, 2020
Priority date	Dec 16, 2019
Publication date	Mar 26, 2024
Grant date	Mar 26, 2024

Abstract

An optical operating fluid detector for optical detection of operating fluid for a hand-guided garden, forestry and/or construction machining appliance includes a light source, an operating fluid line and a light receiver. The light source is designed for radiation of rays of light. The operating fluid line is designed for optical interaction of rays of light from the light source with operating fluid in line for the optical detection of operating fluid. The light receiver is designed for differing reception of rays of light from the line in dependence on the presence or the absence of operating fluid in the line. The operating fluid detector has an optical deflecting device. The deflecting device is designed for deflection of rays of light from the light source to the operating fluid line and/or for deflection of rays of light from the line to the light receiver. The operating fluid line is designed for differing diversion of rays of light from the light source in dependence on the presence or the absence of operating fluid in the line for optical detection of operating fluid.

First claim

What is claimed is:

1. A hand-guided garden, forestry and/or construction machining appliance, comprising:
an operating fluid tank, the operating fluid tank being designed for storage of operating fluid;
an operating fluid pump, the operating fluid pump being designed for delivery of operating fluid from the operating fluid tank; and
an optical operating fluid detector for optical detection of operating fluid for the hand-guided garden, forestry and/or construction machining appliance, the operating fluid detector comprising:
a light source, the light source being designed for radiation of rays of light;
an operating fluid line, the operating fluid line being designed for optical interaction of the rays of light from the light source with operating fluid in the operating fluid line for the optical detection of operating fluid; and
a light receiver, the light receiver being designed for differing reception of rays of light from the operating fluid line in dependence on a presence or absence of operating fluid in the operating fluid line, wherein

the operating fluid detector has at least one optical deflecting device, the at least one optical deflecting device being designed for deflection of the rays of light from the light source to the operating fluid line and/or for deflection of the rays of light from the operating fluid line to the light receiver,
the operating fluid line is designed for differing diversion of the rays of light from the light source in dependence on the presence or the absence of operating fluid in the operating fluid line for the optical detection of operating fluid,
an inner surface of the operating fluid line is designed for the differing refraction of the rays of light from the light source in dependence on the presence or the absence of operating fluid in the operating fluid line for the optical detection of operating fluid,
the operating fluid detector has an optical body, the body having the operating fluid line and the at least one optical deflecting device,
the operating fluid detector has a printed circuit board,
the printed circuit board carries the light source, the light receiver, and the body,
the light source is aligned for the radiation of the rays of light away from a board plane of the printed circuit board,
the light receiver is aligned for the reception of the rays of light from the operating fluid line towards the board plane,
the operating fluid line is connected downstream of the operating fluid tank and upstream or downstream of the operating fluid pump,
the garden, forestry and/or construction machining appliance has a machining tool, and
the operating fluid pump is designed for the delivery of operating fluid to the machining tool for lubricating the machining tool with operating fluid in the form of lubricating fluid.

2. The hand-guided garden, forestry and/or construction matching appliance according to claim 1 , wherein
the at least one optical deflecting device is designed for deflection based on reflection.

3. The hand-guided garden, forestry and/or construction machining appliance according to claim 2 , wherein
the at least one optical deflecting device is a mirror.

4. The hand-guided garden, forestry and/or construction machining appliance according to claim 3 , wherein
the mirror is a concave mirror or a parabolic mirror.

5. The hand-guided garden, forestry and/or construction machining appliance according to claim 2 , wherein
the at least one optical deflecting device has at least one point of a surface of the body a reflection coating.

6. The hand-guided garden, forestry and/or construction machining appliance according claim 1 , wherein
the light receiver is aligned for the reception of the rays of light from the operating fluid line orthogonally towards the board plane.

7. The hand-guided garden, forestry and/or construction machining appliance according to claim 6 , wherein
the operating fluid detector has a sealing compound, the sealing compound protecting the light source, the light receiver, the at least one optical deflecting device, and/or the printed circuit board.

8. The hand-guided garden, forestry and/or construction machining appliance according to claim 1 , wherein
the operating fluid line is aligned in such a way that the rays of light from the light source impinge on an inner surface of the operating fluid line, non-parallel, in relation to the operating fluid line.

9. The hand-guided garden, forestry and/or construction machining appliance according to claim 1 , wherein
a refractive index of a wall of the operating fluid line is greater than 1 and/or similar to a refractive index of the operating fluid.

10. The hand-guided garden, forestry and/or construction machining appliance according to claim 1 , wherein
the operating fluid detector is designed in such a way that the light receiver receives more rays of light from the operating fluid line in the case of the presence of operating fluid in the operating fluid line than in the case of the absence of operating fluid in the operating fluid line.

11. The hand-guided garden, forestry and/or construction machining appliance according to claim 1 , wherein
the light receiver is designed for measurement of an intensity of the received rays of light, and
the operating fluid detector has an output device, the output device being designed for the output of a detection signal when a detection intensity limit value is reached and/or overshot by the measured intensity and/or for the output of a non-detection signal when a non-detection intensity limit value is undershot by the measured intensity.

12. The hand-guided garden, forestry and/or construction machining appliance according to claim 1 , wherein
the operating fluid detector has an output device, the output device being designed for the output of a detection signal when there is detection of operating fluid for a first minimum time period and/or for the output of a non-detection signal when there is non-detection of operating fluid for a second minimum time period.

13. The hand-guided garden, forestry and/or construction machining appliance according to claim 12 , wherein
the operating fluid detector has a sealing compound, the sealing compound protecting the light source, the light receiver, the at least one optical deflecting device, and/or the output device.

14. The hand-guided garden, forestry and/or construction machining appliance according to claim 1 , wherein
the operating fluid detector is designed in such a way that, with a radiating light source, the light receiver receives rays of light in the case of the presence and in the case of the absence of operating fluid in the operating fluid line, and
the operating fluid detector has an output device, the output device being designed for the output of a fault signal in the case of non-reception.

15. The hand-guided garden, forestry and/or construction machining appliance according to claim 1 , wherein
the operating fluid line is straight from a line inlet up to a line outlet of the operating fluid line.

16. The hand-guided garden, forestry and/or construction machining appliance according to claim 1 , wherein
the operating fluid detector has a sealing compound, the sealing compound protecting the light source, the light receiver and/or the at least one optical deflecting device.

17. A hand-guided garden, forestry and/or construction machining appliance, comprising:
an operating fluid tank, the operating fluid tank being designed for storage of operating fluid;
an operating fluid pump, the operatin

Assignees

• Stihl Ag & Co Kg Andreas

Inventors

• Haas Alexander
• Pulfer Michael

Classifications

• G01F23/2927 Primary

  for several discrete levels, e.g. with more than one light-conducting sensing element · CPC title

• B27B17/12

  Lubricating devices specially designed for chain saws · CPC title

• G01V8/10 Primary

  Detecting, e.g. by using light barriers (by reflection from the object G01S17/00) · CPC title

• G01F23/2925 Primary

  using electrical detecting means · CPC title

• G01F1/661

  using light · CPC title