JPH041357Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to an electric pump that is driven by a dry battery or the like and transfers liquid, and in particular a type of device that automatically stops depending on the level of the liquid being transferred. Regarding.

[Prior art and its problems] As this type of electric pump with an automatic liquid level stop device, one using an optical liquid level switch is known, for example, as shown in Japanese Patent Application Laid-Open No. 54-57203. There is.

Incidentally, most of the liquid level switches in such conventional devices are enclosed in a prism cylinder having a prism formed at its tip, and are fastened and fixed to a housing portion at the tip of a discharge hose with a screw or the like. However, in such a fixing structure, stress concentration occurs in the tightening portion due to deformation of the prism cylinder due to material deterioration, which may cause cracks or the like, allowing liquid to enter the cylinder and causing malfunction.

A possible solution to this problem is to fix the prism cylinder by fitting it into the storage part, but as the liquid level rises, the liquid must flow smoothly into the storage part, and the inner wall of the storage part and the outer periphery of the prism cylinder need to flow smoothly. It was necessary to ensure a sufficient liquid flow gap between the two. In other words, if a sufficient flow gap is not secured, when air bubbles enter the housing, they will not be able to pass through the narrow gap with the prism cylinder and will remain, and if the liquid level has reached the detection level but the detection cannot be performed, This caused malfunctions.

[Means for Solving the Problems] This invention includes a storage tube formed near one side of the distal end of the discharge hose, and a container that is housed in the storage tube,
A prism tube having a conical tip formed as a prism and enclosing a light-emitting element and a light-receiving element facing each other; a flange supported substantially concentrically within the housing tube; a vent hole bored in the wall of the discharge hose adjacent to the housing tube to open the inside of the housing tube to the atmosphere; The above-mentioned problem is solved by including a protrusion that contacts the inner wall of the cylinder on the side where the ventilation hole is formed and holds the prism cylinder in an inclined state with respect to the storage cylinder.

[Examples] Examples will be described below based on the drawings. 1 is a pump body, 2 is a base cylinder, and a suction pipe 3 is attached to the base cylinder 2.
and a discharge hose 4 are attached in communication with each other. 5 is a battery case attached to the base tube 2. 6 is a battery serving as a power source, and 7 is a pump, which is a submerged pump in the illustrated example, and is provided at the tip of the suction pipe 3 to lead the power source of the battery 6 in the battery case 5 via a switch 8. 9 is the motor of the submersible pump 7;
10 is a pump blade, and 11 is a flow path. Reference numeral 12 denotes a hollow housing tube formed to one side inward of the tip of the discharge hose 4. Inside the tube 12 is a prism tube 13 made of transparent synthetic resin or the like and having a prism 13 with a conical tip. 15 is installed. Further, the prism tube 15 has a hollow interior except for the prism 13, and a light emitting element 16 and a light receiving element 17 are provided inside the prism tube 15 so as to face the prism surface. 18 is a sealing material that prevents liquid from flowing into these elements 16 and 17, and 19 is a wiring cord.
Reference numeral 20 denotes a projection formed on a part of the outer peripheral surface of the prism tube 15. When the prism tube 15 is inserted into the storage tube 12, the projection 20 is positioned on the side of the ventilation hole 21 provided in the wall of the storage tube 12. , the protrusion 20 is in contact with the inner wall of the storage tube 12, and the prism tube 15 is in contact with the ventilation hole 2.
Tilt in the opposite direction to 1. As a result, the gap 22 between the wall of the storage tube 12 on the side of the ventilation hole 21 and the prism tube 15 becomes wider than the others, making it easier for air bubbles that have entered the storage tube 12 to be discharged from the ventilation hole 21. 23
is a flange formed at the base end of the prism tube 15, which bulges outward and comes into contact with the inner surface of the prism tube 15 when inserted into the housing tube 12, and supports the prism tube 15 substantially concentrically with the housing tube 12 at this base. A switching device 24 performs a switching operation in response to a signal from the light receiving element 17 that receives the light projected by the light emitting element 16, and controls the operation of the motor 9 of the pump 7.

[Effects of the invention] This invention is constructed as described above, and since the flange of the prism cylinder is supported in contact with the inner surface of the housing cylinder, there is no need to tighten and fix it with screws, etc.
It can operate reliably over a long period of time without worrying about cracking due to stress concentration. In addition, by tilting the prism tube with the protrusion, a wider gap can be secured between the inner wall of the storage tube on the side where the ventilation hole is provided and the prism tube than on the other side, so even if air bubbles enter the storage tube, they will not stay there. It is possible to discharge the air through the ventilation hole, which eliminates malfunctions.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of the configuration of this invention. FIG. 2 is a sectional view of the prism tube. FIG. 3 is a configuration diagram of the prism cylinder section. 1 is a pump main body, 3 is a suction tube, 4 is a discharge hose, 7 is a pump, 12 is a storage tube, 13 is a prism, 15 is a prism tube, 16 is a light emitting element, 17 is a light receiving element, 20 is a protrusion, 21 is Vent hole, 23 is a flange.

Claims (1)

[Scope of utility model registration request] In an electric pump that has a suction pipe and a discharge hose and transfers liquid by a motor, a storage cylinder formed near one side of the distal end of the discharge hose;
A prism tube is housed in the storage tube and has a conical tip to form a prism, and a light emitting element and a light receiving element are enclosed opposite the prism. a flange that is in contact with the inner surface of the cylinder and supports the prism cylinder substantially concentrically within the storage cylinder; a vent hole that is bored in the wall surface of the discharge hose adjacent to the storage cylinder and opens the inside of the storage cylinder to the atmosphere; and the prism cylinder. an electric pump, comprising: a protrusion provided on the outer periphery of the housing cylinder for holding the prism cylinder in an inclined state with respect to the housing cylinder by contacting the inner wall of the storage cylinder on the side where the ventilation hole is formed.