A real AI-drafted provisional, and what it got wrong

One unedited run of iPatent (@cf/openai/gpt-oss-120b, 39 seconds) on a five-sentence description of a folding drawer hinge. The structure is useful. Several facts are invented, and the support map catches the ones in the claims.

What the inventor typed

What the run got wrong

Support map: 7 of 9 claim elements supported, 2 unsupported

distinctive-term overlap with the best numbered paragraph, and every number in a claim must appear in the specification; a check on wording, not a legal opinion

The draft, unedited

Technical field

[0001] The present disclosure relates to furniture hardware, and more specifically to a hinge mechanism for drawer fronts that permits the front to fold flat against a cabinet side while providing a biasing force to close the drawer.

Background

[0002] Conventional drawer hinges are mounted on the exterior of a cabinet and protrude from the cabinet face, consuming valuable interior clearance in narrow or high‑density cabinet assemblies. In many cabinet configurations the hinge geometry limits the maximum opening angle of the drawer front, restricting ergonomic access. A need therefore exists for a compact hinge that occupies minimal space, allows the drawer front to lie flush with the cabinet side when opened, and automatically returns the front to a closed position.

Summary

[0003] The invention provides a compact folding hinge comprising a steel mounting plate secured to a cabinet frame, a cylindrical pivot pin extending through a sleeve on the plate, and a torsion spring wound about the pin that biases the drawer front toward the closed position. The pivot pin may be fabricated from stainless steel (≈6 mm diameter) or brass, and the torsion spring may be replaced by an elastomeric bushing to achieve a comparable restoring torque. When the drawer front is pulled past approximately ninety degrees, the hinge folds such that the front lies substantially coplanar with the cabinet side, thereby eliminating protrusion.

[0004] The hinge is installed with two screws, and the spring or bushing is pre‑loaded during assembly to provide a predetermined closing torque. The disclosed hinge achieves a reduced profile, a simple two‑screw attachment, and a self‑closing action without additional actuators.

Detailed description

[0005] The hinge assembly includes a planar mounting plate (10) formed of cold‑rolled steel, having a centrally located cylindrical sleeve (12) of internal diameter matching the outer diameter of the pivot pin (14). The mounting plate is affixed to the cabinet frame (16) by two self‑tapping wood screws (18) spaced to align the sleeve with the hinge axis. The pivot pin (14) is a solid rod, preferably stainless steel, 6 mm in diameter and 30 mm in length, extending through the sleeve and projecting outward on both sides of the plate.

[0006] A torsion spring (20) of rectangular cross‑section is wound around the exposed portion of the pin; one end of the spring is anchored to a retaining collar (22) fixed to the plate, while the other end is fixed to a second collar (24) that rotates with the pin. During assembly the spring is pre‑twisted to store elastic energy, thereby generating a clockwise torque that urges the drawer front (26) toward the closed position. An alternative embodiment replaces the torsion spring with an elastomeric bushing (28) positioned within the sleeve; the bushing is compressed during assembly to provide a similar restoring torque.

[0007] When the user pulls the drawer front beyond a ninety‑degree angle, the pin rotates within the sleeve, allowing the front to fold flat against the cabinet side (30). The hinge returns to the closed orientation when the user releases the front, as the stored spring or bushing energy drives the pin back to its neutral position. The entire assembly occupies a thickness of less than 12 mm, permitting installation in cabinets with limited clearance.

Claims

1. An apparatus comprising:

a mounting plate having a planar surface adapted to be fixed to a cabinet frame and a cylindrical sleeve extending from the planar surface;

a pivot pin extending through the sleeve, the pin having a first end and a second end extending outward from opposite sides of the plate;

a torsion spring wound about at least a portion of the pivot pin between the first end and the second end, the spring being pre‑loaded to bias the pivot pin toward a first angular position;

wherein the apparatus is configured such that when a drawer front attached to the pivot pin is rotated past approximately ninety degrees relative to the cabinet frame, the drawer front folds substantially coplanar with the cabinet side, and the stored energy in the torsion spring returns the drawer front toward the first angular position when external force is removed.

2. The apparatus of claim 1, wherein the mounting plate is fabricated from steel and the pivot pin is fabricated from stainless steel having a diameter of about 6 mm.

3. The apparatus of claim 1, wherein the torsion spring is a rectangular‑cross‑section spring having a calibrated torque of between 0.5 N·m and 2.0 N·m.

4. The apparatus of claim 1, further comprising two screws for securing the mounting plate to the cabinet frame.

5. The apparatus of claim 1, wherein the torsion spring is replaced by an elastomeric bushing positioned within the sleeve, the bushing being compressed during assembly to provide a biasing torque.

6. The apparatus of claim 5, wherein the elastomeric bushing is composed of silicone rubber having a Shore A hardness of 40–60.

Abstract

A compact folding hinge for drawer fronts is disclosed. The hinge includes a steel mounting plate fixed to a cabinet frame by two screws, a cylindrical pivot pin that passes through a sleeve on the plate, and a torsion spring wound about the pin to provide a biasing torque that closes the drawer. When the drawer front is pulled past approximately ninety degrees, the hinge folds so that the front lies substantially flat against the cabinet side, eliminating protrusion and conserving interior space. Alternative embodiments replace the torsion spring with an elastomeric bushing to achieve comparable restoring force. The hinge occupies less than 12 mm of thickness, can be installed with standard hardware, and is suitable for narrow‑width cabinets where conventional hinges waste valuable space. The disclosure also provides a method of assembly, a system incorporating the hinge, and a computer‑readable medium containing instructions for automated manufacturing.

Reviewer notes from the model (support gaps)

- Exact material specifications for the elastomeric bushing (e.g., durometer, dimensions) are not fully described; additional data needed for a skilled artisan to select an appropriate substitute. - No quantitative relationship is provided between the number of torsion‑spring turns and the resulting closing torque; calculations or tables would aid enablement. - The method of pre‑loading the torsion spring during assembly is described only qualitatively; a step‑by‑step procedure (e.g., torque wrench values, fixture design) is absent. - Drawings referenced (FIG. 1, FIG. 2) are not supplied; the disclosure should include: * FIG. 1 – exploded view of the hinge components in the closed position; * FIG. 2 – side view showing the drawer front folded flat against the cabinet side; * FIG. 3 – cross‑section illustrating the elastomeric‑bushing embodiment. - The claim set includes a computer‑readable medium, but the inventor’s description does not provide any software logic or algorithmic detail; further elaboration would be required to satisfy written‑description support. - No discussion of tolerances for the sleeve‑pin fit or the effect of wear over time; these parameters should be defined to ensure reliable operation. - The protective coating mentioned in claim 14 is not described (type of coating, application method). If any of the above items are unavailable or unnecessary, the inventor should confirm so that the provisional application can be refined accordingly.