Patent Description:
Research has shown that cats can provide emotional support, improve moods, and contribute to the overall morale of their owners. As a result, cats are a great choice of pet.

Many automatic cat litter boxes have been around for a while. Typically, an automatic cat litter box includes a geared base and a roller. When in use, cat litter particles may tend to enter the tooth spaces of the gears of the base and the roller, and the space between the base and the roller. If cat litter particles fall into the tooth spaces, it may cause gear jamming. If cat litter particles fall into the space between the base and the roller, they may scratch the outer lateral surface of the roller, or even case the roller to be stuck.

Therefore, there is a need to provide a pet litter device to overcome the above-mentioned problems. <CIT> describes a pet toilet capable of preventing friction between a sand bin and pet sand particles falling between the sand bin and a base. <CIT> discloses a cat litter box. <CIT> discloses a litter collection device for sifting animal waste using an improved sifting method. <CIT> discloses an improved litter device for use by animals that automatically removes animal waste from litter. <CIT> comprises a weight measuring mechanism and constitutes the state of the art closest to the subject-matter of claim <NUM>.

Many aspects of the present embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present embodiments. Moreover, in the drawings, all the views are schematic, and like reference numerals designate corresponding parts throughout the several views.

The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings, in which like reference numerals indicate similar elements. It should be noted that references to "an" or "one" embodiment in this disclosure are not necessarily to the same embodiment, and such references can mean "at least one" embodiment.

Referring to <FIG>, a pet litter device <NUM> is provided for use with pets such as dogs and cats. The device <NUM> includes a base <NUM> and a drum <NUM>. Referring to <FIG>, the base <NUM> defines a recessed portion <NUM> in a surface (e.g., upper end surface in <FIG>) facing the drum <NUM>. The drum <NUM> is partly and rotatably received in the recessed portion <NUM>. The recessed portion <NUM> has a recess surface <NUM> defining an opening <NUM>. The opening <NUM> is under the drum <NUM>. The recess surface <NUM> and a portion of the outer lateral surface <NUM> of the drum <NUM> that faces the recess surface <NUM> define a gap d therebetween and form a passage <NUM> in communication with the opening <NUM>. The recess surface <NUM> is to guide litter particles entering the passage <NUM> to pass through the opening <NUM> to fall on the support surface <NUM> (see <FIG>) where the device <NUM> is placed. The support surface may be the ground, a table top, or other surfaces capable of supporting the device <NUM>.

Referring to <FIG>, in one embodiment, the drum <NUM> can be cylindrical and supported by four rollers <NUM> partly received in the recess surface <NUM>. One end of the drum is provided with a transmission gear that meshes with the output gear <NUM> of a drive motor, and rotates in place on the base <NUM> under the driving of the output gear <NUM> of the drive motor.

If tiny objects (e.g., cat litter particles) enter the passage <NUM>, they will be guided by the recess surface <NUM>, pass through the opening <NUM>, and finally fall on support surface where the device <NUM> is placed. A user can then clean up the tiny objects (e.g., cat litter particles) on the support surface.

Compared with some conventional pet litter devices that requires the drum to be disassembled from the base when it needs to clean up litter particles between the base and the drum, the litter particles entering the passage <NUM> can automatically move out of the device <NUM> through the opening <NUM>, which can free a user from manually disassembling the drum <NUM> from the base <NUM>. Since the litter particles entering the passage <NUM> between the drum <NUM> and the recessed portion <NUM> can directly fall on the support surface, the litter particles will not accumulate between the drum <NUM> and the recessed portion <NUM>, which can prevent the output gear <NUM> of the drive motor and the transmission gear from being jammed. This also avoids the problem that the litter particles accumulated between the drum <NUM> and the base <NUM> cause friction or adversely affect the rotation of the drum <NUM>.

In one embodiment, an area of the opening <NUM> and an area of a cross-section of a portion of the drum <NUM> received in the recessed portion <NUM> satisfy the following relationship: 3A/<NUM>≤S≤2A/<NUM>, where S represents the area of the opening <NUM>, and A represents the area of the cross-section of a portion of the drum <NUM> received in the recessed portion.

In one embodiment, the opening <NUM> is a rectangular through hole, and the area of the opening <NUM> is equal to the product of the length and the width of the opening <NUM>. The cross-section of a portion of the drum <NUM> received in the recessed portion means a transverse section of the drum <NUM> taken parallel to a horizontal surface when the device <NUM> is placed on the horizontal surface.

The limitation on the area of the opening <NUM>, that is, the limitation on the size of the opening <NUM>, can avoid the problem that tiny objects (e.g., cat litter particles) entering the passage <NUM> cannot easily fall from the opening <NUM> due to the small size of the opening <NUM>. By limiting the proportion of the size of the opening <NUM> to the portion of the drum <NUM> received in the recessed portion <NUM>, the tiny objects entering the passage <NUM> can fall on the support surface easily.

As shown in <FIG>, in one embodiment, the recess surface <NUM> extends downwardly from a top end <NUM> of the base <NUM>. The recess surface <NUM> can be an inclined surface or a concave surface.

In the embodiment, since the recess surface <NUM> is an inclined surface or a concave surface, the recessed portion <NUM> provides a ramp when the device <NUM> is placed on a horizontal surface. With such configuration, the tiny objects (e.g., cat litter particles) that enters the passage <NUM> can slide down the recess surface <NUM> toward the opening <NUM>, and then pass through the opening <NUM> and fall on the support surface, which can avoid the problem that the litter particles accumulated between the drum <NUM> and the base <NUM> cause friction or adversely affect the rotation of the drum <NUM>.

Referring to <FIG>, in one embodiment, the passage <NUM> has an inlet <NUM> formed between a top end <NUM> of the base <NUM> and the outer lateral surface <NUM>, and an outlet <NUM> (see <FIG>) formed between an edge of the opening <NUM> and the outer lateral surface <NUM>. The inlet <NUM> is smaller in size than the outlet <NUM>.

By setting the size of the inlet <NUM> of the passage <NUM> to be smaller than the size of the outlet of the passage <NUM>, that is, by adopting a non-uniform design with narrow inlet and wide outlet, it allows the tiny objects (e.g., cat litter particles) to smoothly fall on the support surface through the opening <NUM>. Specifically, at the inlet of the gap d (i.e., the inlet <NUM> of the passage <NUM>) between the drum and the base <NUM>, the gap d can be set to <NUM>, and the gap d gradually increases from the inlet to the opening <NUM>. In this way, because the gap d gradually increases from the inlet to the opening <NUM>, it is ensured that cat litter particles can smoothly move to the through hole <NUM> after they enter the inlet of the gap d.

In one embodiment, the area of the longitudinal section of the object channel <NUM> gradually increases from the inlet <NUM> of the passage <NUM> to the outlet of the passage <NUM>.

Here, the longitudinal section of the passage <NUM> is taken perpendicular to a horizontal surface when the device <NUM> is placed on the horizontal surface. The area of the longitudinal section of the passage <NUM> gradually increases from the inlet <NUM> to the outlet, which follows the design principle of narrow inlet and wide outlet. Such a design makes it difficult for external objects to pass through the inlet <NUM> of the passage <NUM>, and once tiny objects such as cat litter particles enter the passage <NUM>, then can smoothly fall on support surface through the opening <NUM> along the passage <NUM>.

Referring to <FIG>, the device <NUM> further includes a weight measuring mechanism <NUM> that is arranged in the base <NUM> and is to measure a weight of the drum <NUM>. When a pet (e.g., a cat) enter a pet access portal of the device <NUM>, the measured weight will dramatically change. Based on the change in weight, the device <NUM> can determine that a pet has entered the pet access portal of the device <NUM>.

The weight measuring mechanism <NUM> includes a support member <NUM>, a weight sensor <NUM>, and a leg <NUM>. The support member <NUM> is arranged in the base <NUM>. The weight sensor <NUM> is connected to and arranged under the support member <NUM>. For example, the weight sensor <NUM> is fixed to the support member <NUM> by screws. In another embodiment, the weight sensor <NUM> can be fixed to the support member <NUM> by glue or other adhesive medium.

The weight sensor <NUM> is connected to and arranged above the leg <NUM>. The leg passes through the base <NUM> to be in contact with the support surface. When the device <NUM> is placed on the support surface (e.g., a floor), the leg <NUM> is in contact with the support surface. The leg <NUM> supports the weight sensor <NUM>, and the base <NUM>, the drum10 and the weight sensor <NUM> press down the leg <NUM>. At this time, the whole weight acts on the weight sensor <NUM> and transmitted to the leg <NUM> and the support surface. The whole weight can then be measured by the weight sensor <NUM>.

Referring to <FIG>, in order to better support the weight sensor <NUM> and make the triggering of the weight sensor <NUM> more sensitive, the leg <NUM> may be provided a contact member <NUM> under the weight sensor <NUM>. When the leg <NUM> is in contact with the support surface, the contact member <NUM> is in contact with the weight sensor <NUM>. At this time, the whole weight acts on the weight sensor <NUM> and is transmitted to the leg <NUM> and the support surface.

In one embodiment, the contact member <NUM> are made of hard material, such as metal or plastic material.

It should be noted that the weight sensor <NUM> is electrically connected to a controller of the device <NUM>. The controller may control the data measured by the weight sensor <NUM> on a display of the device <NUM>. The controller and the display are conventional, which are not detailed here.

As shown in <FIG> and <FIG>, the base <NUM> includes an upper housing <NUM> and a lower housing <NUM> that are connected to each other, for example, by screws. The upper housing <NUM> defines the recessed portion <NUM>, and the opening <NUM> passes through the upper housing <NUM> and the lower housing <NUM>.

It should be noted that the shape of the opening <NUM> can be chosen according to actual needs, such as a circle, a square, an ellipse, a trapezoid, and the like.

The lower housing <NUM> defines a chamber <NUM> and a through hole <NUM> in communication with the chamber <NUM>. For example, the through hole <NUM> may be located in the bottom of the chamber <NUM>. The support member <NUM>, the weight sensor <NUM>, and the leg <NUM> are arranged, from top to bottom, in the chamber <NUM>. The support member <NUM> is securely connected to the upper housing <NUM>, and the leg <NUM> movably passes through the through hole <NUM>. Thus, the support member <NUM>, the weight sensor <NUM> and the leg <NUM> can be held in position.

Referring to <FIG> and <FIG>, in one embodiment, the leg <NUM> defines a receiving space <NUM> to receive the weight sensor <NUM> and includes two first hooks <NUM> that engage an upper side <NUM> of the weight sensor <NUM> to prevent the leg <NUM> from moving away from the support member <NUM>. In one embodiment, the two first hooks <NUM> protrude from the upper end surface of the leg <NUM> and are opposite each other and adjacent to the receiving space <NUM>.

In one embodiment, the weight sensor <NUM> is fixed to the support <NUM>, and the weight sensor <NUM> is partly received in the receiving space <NUM> of the leg <NUM>. When the device <NUM> is placed on the support surface, the leg <NUM> can move up a short distance so that the leg <NUM> can apply a push force to the bottom of the weight sensor <NUM>. The first hooks <NUM> do not restrict the upward movement (i.e., moving toward the support <NUM>) of the leg <NUM>.

As shown in <FIG>, in one embodiment, the two limit walls <NUM> protrude from the upper end surface of the leg <NUM> toward the support member <NUM>, and a groove <NUM> is defined in the weight sensor <NUM>. The groove <NUM> extends along the periphery of the top of the weight sensor <NUM>. The limit walls <NUM> pass through the groove <NUM> and abut against the inner surface of the groove <NUM>. The limit walls <NUM> are to limit the movement of the weight sensor <NUM> in a direction parallel to the support surface. That is, while the weight sensor <NUM> is fixed on the support member <NUM>, the limit walls <NUM> limit the movement along the top the load weight sensor <NUM>, thereby ensuring the reliability of assembly.

In one embodiment, in order to prevent the horizontal movement of the weight sensor <NUM> and affect the measurement accuracy, a protrusion <NUM> is protruded from the upper end surface of the leg <NUM> toward the support member <NUM>. Specifically, the protrusion <NUM> is located on the side opposite to the limit walls <NUM>. When the weight sensor <NUM> moves toward the protrusion <NUM>, the edge of the weight sensor <NUM> will abut against the protrusion <NUM>, thereby restricting the weight sensor <NUM> from continuing to move toward the protrusion <NUM>.

Referring to <FIG> and <FIG>, in one embodiment, the weight sensor <NUM> can be connected to the support member <NUM> by a fastener (e.g., a screw) or adhesive bonding. The support member <NUM> may include a second hook <NUM> that engages a lower side <NUM> of the weight sensor <NUM> to prevent the weight sensor <NUM> from moving away from the support member <NUM>. In this way, the weight sensor <NUM> is fixed to the support member <NUM>, and the connection strength between the support member <NUM> and the weight sensor <NUM> is increased.

Referring to <FIG>, in one embodiment, the device may include a support assembly that includes a number of support members <NUM> and legs <NUM>. The support members <NUM> are fixed to the base <NUM>. The legs <NUM> are connected to the support members <NUM> and pass through the base <NUM>, and the legs <NUM> can support the base <NUM> on the support surface.

In one embodiment, two lugs <NUM> are provided on each leg <NUM> adjacent to a corresponding support member <NUM>. Each leg <NUM> is connected to a corresponding support member <NUM> by a bolt passing through the lug <NUM> of the leg <NUM>. In addition, the support members <NUM> and the legs <NUM> have the above-described structure for holding weight sensors <NUM> in position. In the case where weight sensors <NUM> are omitted, the support members <NUM> and the legs <NUM> are connected to each other, respectively, to form the support assembly. In this way, the support members <NUM> and the legs <NUM> can be compatible with a first mode without the weight sensors <NUM> and a second mode with the weight sensors <NUM>, which can save costs and increase product diversity.

In one embodiment, the number of the legs <NUM> is four, and the number of the support members <NUM> is four. However, the numbers of the legs <NUM> and the support members <NUM> may change according to actual needs.

In one embodiment, the bottom of each leg <NUM> is provided with an anti-slip pad <NUM>, and the anti-slip pad <NUM> is flat. On the one hand, the anti-slip pads <NUM> can prevent the device <NUM> from slipping and moving sideways when placed on the support surface. On the other hand, the anti-slip pads <NUM> are flat, which to make them more stable when they are in contact with the support surface.

In summary, embodiments of the present disclosure provide a pet litter device that includes a drum <NUM> rotatably and partly received in the recessed portion <NUM>. The recess surface <NUM> and a portion of the outer lateral surface <NUM> of the drum <NUM> that faces the recess surface <NUM> define a gap d therebetween and form a passage <NUM> in communication with the opening <NUM>. If tiny objects (e.g., cat litter particles) enter the passage <NUM>, they will be guided by the recess surface <NUM>, pass through the opening <NUM>, and finally fall on support surface where the device <NUM> is placed. A user can then clean up the tiny objects (e.g., cat litter particles) on the support surface. Since the litter particles entering the passage <NUM> between the drum <NUM> and the recessed portion <NUM> can directly fall on the support surface, the litter particles will not accumulate between the drum <NUM> and the recessed portion <NUM>, which can prevent the output gear <NUM> of the drive motor and the transmission gear from being jammed. This also avoids the problem that the litter particles accumulated between the drum <NUM> and the base <NUM> cause friction or adversely affect the rotation of the drum <NUM>.

Claim 1:
A litter device (<NUM>) for a pet, comprising:
a base (<NUM>) configured to be placed on a support surface, the base comprising a recessed portion (<NUM>) that comprises a recess surface (<NUM>) defining an opening (<NUM>);
a drum (<NUM>) rotatably connected to the base and partly received in the recessed portion, the drum comprising an outer lateral surface (<NUM>), the recess surface and a portion of the outer lateral surface that faces the recess surface defining a gap (d) therebetween and forming a passage (<NUM>) in communication with the opening, and the recess surface configured to guide litter particles entering the passage to pass through the opening to fall on the support surface; and
weight measuring mechanism (<NUM>), wherein the weight measuring mechanism is arranged in the base (<NUM>) and is configured to measure a weight of the drum (<NUM>),
wherein the weight measuring mechanism (<NUM>) comprises a support member (<NUM>), a weight sensor (<NUM>), and a leg (<NUM>), the support member is arranged in the base (<NUM>), the weight sensor is connected to and arranged under the support member, the weight sensor is connected to and arranged above the leg, and the leg passes through the base to be in contact with the support surface, and
wherein the base (<NUM>) comprises an upper housing (<NUM>) and a lower housing (<NUM>) that are connected to each other, the upper housing defines the recessed portion, the opening passes through the upper housing and the lower housing, the lower housing defines a chamber (<NUM>) and a through hole (<NUM>) in communication with the chamber, the support member, the weight sensor, and the leg are arranged in the chamber, the support member is securely connected to the upper housing, and the leg passes through the through hole.