Automatic chinchilla sander and cleaner

This invention consists of an automatic device used in the raising of chinchillas to allow the animals to sand themselves in a bath of sand, and at the same time to clean said sand from the animal feces. The device consists of a stationary, vertical, circular box having a screen therein which rotates on an inner and outer central shafts pinned together when rotation is required. One position of the screen prevents the animal from entering the device, and another position allows the animal to enter and reach the sand. After a predetermined sanding time, the screen reverses itself, scoops up and discharges the animal, and sifts the sand clean of feces, and returns it to its original location. A clutch is provided to allow rotation when the screen limits are reached. Power is supplied manually, or by a speed reduced motor. And the periods and duration of sanding is controlled by an electric timing device where a motor is used. A quick attachment and release coupling is provided for joining several of the devices together.

This invention relates generally to devices used in the care of fur-bearing 
animals which are being raised on farms, and particularly to the sanding 
and sand cleaning operation required in the raising of chinchillas. 
Among all the necessary conditions required in the breeding and raising of 
healthy, rich fur-bearing chinchillas, is the need of this animal to sand 
itself in a specific type of sand which must be supplied by the breeder. 
This sand must be available to the animals at regular intervals, for 
definite periods of time, and in a clean condition. 
On a farm where a large number of animals are being raised, the cleaning of 
the sand from the feces of the animals and any other materials which may 
be harmful to them, and the matter of keeping track of the numerous and 
various cages, becomes a difficult and time consuming job. 
It is therefore the object of this invention to provide an automatic, self 
cleaning sanding box which will permit the animal to enter the sanding 
area at predetermined regular intervals, for predetermined periods of 
time, which will remove the animal at the completion of the sanding period 
and discharge it back into the cage, and which will sift the sand clean, 
all in one operation.

In the drawings the invention is shown consisting of a vertical circular 
box 1 having an open entry 2. The box stands upright on legs 3. Running 
through the box 1 is a central shaft consisting of an inner solid shaft 4 
which rotates freely within an outer hollow shaft 5. 
Attached to the outer shaft 5 is a rectangular screen 13 which has a width 
slightly under that of the interior of the box 1, so that it can rotate 
freely therein. This screen has a main rectangular central section 13, an 
inwardly bent shorter section 15, and a lower hinged section 14 which is 
provided with a scraper 30 at its free end. The screen is reinforced in 
the rear with a wire grid 21, and is provided with brackets 20 by means of 
which it is rigidly attached to the outer shaft 5. 
Rotation is provided to the inner shaft 4 by means of a worm gear speed 
reducer 7 through the medium of a clutch arrangement shown in FIG. 5, 
which consists of a "C"-shaped piece 9 of spring sheet metal material 
which engages a sprocket 8 rigidly attached to the output shaft of the 
reducer 7. When the screen 13 reaches the upper stop 16 or the lower stop 
17 and the rotation continues, the "C"-shaped spring 9 skips over the 
teeth of the sprocket 8 without forcing the said screen to rotate. 
In order for the screen to rotate, the outer shaft 5 is connected to the 
inner shaft 4 by means of a pin 10; and the input worm gear of the reducer 
is rotated manually by means of a shaft 11 to which is attached a handle 
12. The reducer 7 is centrally attached to one face of the box 1 by means 
of a "U"-shaped bracket 6 which contains the said clutch. The handle 12 
can be replaced by an electric motor, in which case a friction clutch 18 
can be provided as as additional precaution or as a replacement for the 
clutch described above. 
The box 1 is also provided with a partition 19. This partition is made 
removable for cleaning purposes. 
In FIG. 1, the screen 13 is shown in the position to permit the animal to 
leave the cage 28 and enter the sand pile 23. The path of the animal is 
indicated by arrows. After the animal has completed its sanding, the 
screen is rotated in a clockwise direction until it is stopped by the stop 
16, where it assumes the position shown in FIG. 4. During this rotation 
the scoop part 14 which is additionally supported by a pair of springs 
22,22, scoops up the sand and the animal. The sand 23 is sifted through 
the screen, and returns in a cleaned condition to its original location, 
while the animal is able to return to its cage as shown by the arrows in 
FIG. 4. 
On a farm where many cages are located in a row, a central motivating unit 
as described in the drawings can provide the above described service to 
all the cages by coupling their shafts 4 to the shaft 4 of the motivating 
unit. A proposed quick attachment and release coupling is shown in FIG. 6, 
where the ends of said shafts are cut in half so that they fit each other 
as shown by 27. A sleeve 24 fits over the joint and is held in position 
against a pin in the shaft by a spring 25 located between the rear of the 
sleeve 24 and a stop 26'. 
A pan 29 is provided at the entrance 2 of the box 1, for collecting the 
screenings resulting from the screening of the sand. 
Where a number of the units are coupled together, any one of the units can 
be disconnected from rotation, when so required, by removing its pin 10. 
On occasion, as for instance during a prolonged absence of the attendant, 
automatic operation of the invention would be required. This is 
accomplished by providing a motorized motivating unit equipped with an 
electrical timing device which will turn the screen in either direction at 
predetermined regular intervals, and will provide a predetermined period 
for sanding. 
From the above description it can be seen that this invention is a great 
time and labor saving device, and at the same time providing means of 
caring for the animals during the absence of an attendant.