Sweeper with fire control

• US 4,571,771 A
• Filed: 08/27/1984
• Issued: 02/25/1986
• Est. Priority Date: 08/27/1984
• Status: Expired due to Term

• Current Assignee: Tennant Company
• Original Assignee: Tennant Company
• Inventors: Worwa, Richard G.
• Primary Examiner(s): MOORE, CHRISTOPHER K
• Application Number:
  US06/644,615
• Time in Patent Office: 547 Days
• Field of Search: 15/319, 15/339, 15/340, 15/347, 55/217
• US Class Current: 15/319
• CPC Class Codes: A47L 11/24 Floor-sweeping machines, motor-driven
• CPC Class Codes: A47L 11/4008 Arrangements of switches, indicators or the like
• CPC Class Codes: A47L 11/4011 Regulation of the cleaning machine by electric means; Control systems and remote control systems therefor
• CPC Class Codes: A47L 11/4013 Contaminants collecting devices, i.e. hoppers, tanks or the like
• CPC Class Codes: A47L 11/4019 Fill level sensors; Security means to prevent overflow, e.g. float valves
• CPC Class Codes: A47L 11/4027 Filtering or separating contaminants or debris
• CPC Class Codes: A47L 9/19 Means for monitoring filtering operation
• CPC Class Codes: A62C 3/00 Fire prevention, containment or extinguishing specially adapted for particular objects or places in oil wells E21B29/08, A62C35/00; in mines or tunnels E21F5/00 ; for nuclear reactors G21C9/04
• CPC Class Codes: E01H 1/0827 Dislodging by suction; Mechanical dislodging-cleaning apparatus with independent or dependent exhaust, e.g. dislodging-sweeping machines with independent suction nozzles combined with blowing E01H1/0872; Mechanical loosening devices working under vacuum
• CPC Class Codes: E01H 1/0863 Apparatus loosening or removing the dirt by blowing and subsequently dislodging it at least partially by suction liquids or semi-liquids E01H1/108; Combined suction and blowing nozzles

Abstract

This is concerned with an improved fire control arrangement for controlling a fire caused by a lighted object, such as a cigarette, being swept into the debris chamber of a power sweeper having a vacuumized dust control system.

Claims

1. In a sweeper, a frame, a debris hopper on the frame with an opening for receiving debris, an air exhaust system connected to the hopper including a vacuum fan for exhausting air from the hopper, a power source on the frame for operating the vacuum fan, means for sensing the temperature of the air flowing through the air exhaust system from the hopper, and means responsive to the temperature sensing means in the air exhaust system for indicating when the air temperature in the air exhaust system has reached a predetermined level.

2. The structure of claim 1 further characterized in that the temperature sensing means is in the inlet to he vacuum fan.

3. The structure of claim 1 further characterized in that the indicating means is constructed and arranged to stop the operation of the vacuum fan when the temperature in the air exhaust system has reached a predetermined temperature.

4. The structure of claim 1 further characterized in that the indicating means is constructed and arranged to open the air connection between the hopper and the fan.

5. The structure of claim 1 further characterized in that the indicating means is constructed and arranged to de-energize the drive from the power source to the vacuum fan.

6. The structure of claim 5 in which the sweeper has a generally horizontal rotary brush on the frame for propelling debris from a surface to be cleaned into the hopper, and further characterized in that the indicating means also de-energizes the drive from the power source to the brush.

7. The structure of claim 1 further characterized in that the sweeper has an inlet door on the opening of the debris hopper, and further characterized in that the indicating means is constructed and arranged to close the inlet door on the debris hopper when the air temperature in the air exhaust system has reached a predetermined level.

8. The structure of claim 1 further characterized in that the indicating means is constructed and arranged to de-energize the power source so as to stop the operation of the vacuum fan.

9. The structure of claim 1 further characterized in that the sweeper is a forward throw sweeper with the debris hopper being positioned ahead of a brush and the opening in the hopper is located in the rear thereof for receiving debris propelled forward by the brush.

10. The structure of claim 1 further characterized in that the sweeper is an over-the-top unit with the debris hopper in the rear.

11. The structure of claim 1 further characterized in that the debris hopper is divided into a debris chamber and a filter chamber, an opening between the two chambers controlling the flow of air between the debris chamber and the filter chamber, and means responsive to the temperature sensing means for closing the opening between the two chambers when the air temperature in the air exhaust system has reached a predetermined level.

12. The structure of claim 1 further characterized by and including a conduit between the fan and the hopper in the air exhaust system, and a valve in the conduit constructed and arranged to be closed by the temperature responsive means when the air temperature in the exhaust system has reached a predetermined level.

13. The structure of claim 1 in which the sweeper is of the type having a hopper on a truck and a vacuum fan mounted to exhaust air from the hopper with an air outlet line from the fan outlet connected to a pick-up head adapted to pick up debris from a surface to be cleaned such as a street and an air return line adapted to return air and entrained debris to the hopper, and further characterized in that the temperature sensing means is located in the air outlet line.

14. In a mobile sweeper, a frame, wheels for the frame providing for its movement, a generally horizontal forward throw rotary brush on the frame, a debris receiving hopper on the frame forward of the brush, two chambers in the hopper, one for receiving debris from the brush and another with a filter unit, an opening between the two chambers controlling the flow of air between the debris chamber and the filter chamber, a rear opening in the debris chamber generally opposite the rotary brush adapted to receive debris thrown forward by the brush, an air exhaust system for exhausting air from the hopper including a vacuum fan on the frame connected to the filter chamber, means for sensing the temperature of the air flowing through the air exhaust system from the hopper, and means responsive to the temperature sensing means in the air exhaust system for indicating when the air temperature in the air exhaust system has reached a predetermined level.

15. The structure of claim 14 further characterized in that the indicating means is constructed and arranged to simultaneously close the rear opening of the debris chamber and to vent the exhaust system ahead of the fan when the air temperature in the air, exhaust system has reached a predetermined level.

16. The structure of claim 14 further characterized in that the sensing means is located in the fan inlet.

17. The structure of claim 14 further characterized by and including means responsive to the temperature sensing means for closing the opening between the two chambers.