Paddle for bread-making machine

Abstract: A bread-making machine is disclosed in which a kneading paddle (14) remains in the bucket after the baking cycle. The bread-making machine automatically entraps, or vertically constrains, the kneading paddle (14) to the rotatable drive shaft (11). Upon the initial rotation of the driveshaft (11), the paddle (14) shifts backwardly with respect to the driveshaft under a reactive, inertial force whereby the paddle (14) rotates approximately twenty-five degrees in a counterclockwise direction with respect to the shaft (11). This is made possible by the looseness of the fit of the drive shaft (11) within the paddle's bore (18). A lip (28) positioned on the top of the drive shaft (11) engages a top surface (19) of the paddle hub (16), when the paddle is caused to shift. This engagement captures the paddle (14), causing it to become vertically constrained to the drive shaft (11). Upon completion of the baking cycle, the baked bread can be removed without the paddle, which remains affixed to the drive shaft. The paddle hub (16) has a bore (18) that is approximately rectangular in cross-sectional shape. The bore (18) receives the substantially rectangular drive shaft (11). The paddle (14) is initially deposited over the drive shaft (11), and the dough is placed in the bucket. The paddle (14) is then automatically, vertically locked into place, when the kneading cycle is commenced.

Description: The present invention relates to making bread and, more particularly, to a bread-making apparatus having a paddle that remains in the dough-kneading and bread-baking bucket when the baking cycle is completed and the bread removed therefrom. Recently, bread-making machines have become a quite popular and useful appliance in the home. These machines make fine homemade bread that is fresh, hot and flavourful. Using the bread-making machine is generally simple and convenient. People also enjoy the ability to add particular ingredients to the dough that enhances the flavour of the bread. Most bread-making machines used in the home comprise a dough-kneading bucket that has an electromechanically-driven kneading impeller, or, paddle. In the vast majority of these bread-making machines, the kneaded dough is often embedded in the paddle when the kneaded and baked dough is removed from the bucket, which necessitates the removal of the kneading paddle from the dough. A kneading impeller for a bread-making machine is known from US 5477776 in which the kneading blade or impeller is deposited on the drive shaft, which has a D-shaped cut therein. An abutment surface of the blade engages with the D-shaped surface of the shaft, so that the blade is capable of being rotatively driven thereby. However, a problem with this construction is that the blade does not become vertically constrained to the shaft upon the rotation thereof so it remains removable with the baked bread which is not desirable. It is an object of the present invention therefore to provide an improved bread-making machine in which the kneading blade becomes automatically, vertically constrained upon the drive shaft disposed in the machine's kneading bowl. It is a further object of the invention to provide a bread-making machine with a kneading blade that becomes vertically captured upon the drive shaft disposed in the machine's kneading bowl, without there being the need to resort to expensive components, such as lock detents or snap-action bayonets. The present invention provides a more convenient bread-making apparatus that is free of the need for the user to remove the kneading paddle from the baked bread at the end of the baking cycle as the paddle is retained within the bucket of the machine after the baking cycle is completed. It is known from US-A-5076153 to provide a kneading mechanism for making bread, comprising a bucket for receiving bread dough to be kneaded and baked and a rotatable drive shaft disposed in said bucket for rotating a kneading paddle to knead said bread dough, the drive shaft having a base and abutment means thereon and the kneading paddle having a kneading blade extending from a hub having a top face and a second base and a bore therein for attaching the kneading paddle to the drive shaft, the bore loosely fitting about the drive shaft and being configured so that when the drive shaft is initially actuated, the shaft will shift with respect to the bore under a reactive force, thereby causing the abutment means thereon to ride over and engage the paddle to vertically fix the paddle to the drive shaft. A kneading mechanism according to the present invention is characterised in that when the kneading paddle is attached to the drive shaft the base of the kneading paddle rests upon the base of the drive shaft, the drive shaft having a portion which protrudes beyond the top face of the hub and wherein the abutment means comprises a lip on said protruding portion of the drive shaft which engages with the top face when the drive shaft is initially actuated. This invention automatically retains the paddle within the bucket, without the need for expensive components such as locking detents or snap-acting bayonets. The preferred paddle is designed with an internal, cross-sectional, rectangular-shaped bore. The rotating shaft that drives the paddle is also preferably rectangular in cross-section, and loosely fits within this bore. The looseness of the fit allows the paddle to shift within the bore under reactive inertia, upon actuation of the drive shaft. The drive shaft preferably has a lip that automatically secures the paddle to the shaft, as the paddle is caused to shift. The paddle preferably rotates approximately twenty-five degrees under the aforesaid reactive, inertial force, causing the lip of the shaft to ride over the top surface of the paddle hub and vertically capture the paddle hub upon the drive shaft. Once locked into place, the paddle will remain affixed to the shaft until the bucket and paddle are removed for cleaning. In a preferred embodiment, there is provided a bread-making machine having a kneading paddle that remains in the bucket after the baking cycle. The bread-making machine automatically entraps, or vertically constrains, the kneading paddle to the rotating drive shaft. Upon the initial rotation of the drive shaft, the paddle shifts backwardly with respect thereto, under a reactive, inertial force. The paddle will rotate approximately twenty-five degrees in a counterclockwise direction with respect to the shaft. This is made possible by the looseness of the fit of the drive-shaft within the paddles bore. A lip disposed on the top of the drive-shaft will engage the top surface of the paddle hub, when the paddle is caused to shift. This engagement will capture the paddle, causing it to become vertically constrained to the drive shaft. Upon completion of the baking cycle, the baked bread can be removed without the paddle, which remains affixed to the drive shaft. The paddle hub comprises a bore having an approximately rectangular, cross-sectional shape. The bore receives the substantially rectangular drive shaft. The paddle is initially deposited over the drive shaft, and the dough is placed in the bucket. The paddle is automatically, vertically locked into place, when the kneading cycle is commenced. The invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a perspective, cutaway view of the bucket of the bread-making machine of this invention; Figure 2 is an enlarged view of the drive shaft and kneading impeller-blade that fits within the bucket, shown in Figure 1 with the shaft and the blade illustrated in an unassembled state; Figure 3 is an enlarged view of the drive shaft and kneading impeller-blade that fits within the bucket, shown in Figure 1, with the shaft and the blade depicted in an assembled state; Figure 4 is an enlarged, top view of the kneading impeller-blade of Figure 2 in a locked position; Figure 5 is a sectional view of the kneading impeller-blade of Figure 4 taken along lines A-A thereof; and Figure 6 is a sectional view of the kneading impeller-blade of Figure 5 taken along lines B-B thereof. Generally speaking, the invention features a bread-making apparatus in which, after the baking cycle, a kneading paddle remains temporarily affixed to a rotating drive-shaft. This allows a user to make bread and remove it from the bucket of the machine, without having to remove the blade of the paddle therefrom. In other words, when the bread is removed from the bucket, the kneading paddle remains affixed to the buckets drive shaft. Referring now to Figure 1, a bucket 10 of a bread-making machine is shown in a perspective, cutaway view. A drive shaft 11 for rotating a dough knead-impeller, or, kneading paddle 14 depicted in Figure 2, is disposed at the bottom centre of the bucket 10. Referring to Figure 2, an enlarged view of the drive-shaft 11 is shown, with the kneading impeller or kneading paddle 14 disposed over the shaft 11, in a pre-assembly mode. The kneading paddle 14 comprises a blade portion 15, and a hollow-centre, hub portion 16 that fits over the drive shaft 11, as shown by arrow 17. The bore 18 of the hollow-centre, hub portion 16 of the kneading paddle 14 has a generally rectangularly-shaped hole 18. The top face 19 of the hollow-centre, hub portion 16 can also be observed with reference to Figure 4. Internally, the bore 18 of the hollow-centre, hub portion 16 is approximately rectangular in cross-section (see Figures 4-6). The drive-shaft 11 is shown as having a generally circular, cross-sectioned base 20 that supports a generally rectangular-shaped, upper portion 21. The base 23 of the paddle 14 is caused to rest upon the base 22 of the drive-shaft 11, when assembled thereto (arrow 17). When assembled, the paddle 14 and the shaft 11 are caused to rotate as a single unit by a drive motor (not shown). During the kneading cycle, bread dough (not shown) is placed in the bucket 10. Upon actuation of the bread-making machine, the shaft-and-paddle combination is caused to rotate as aforementioned, thus kneading the dough. Referring to Figure 3, the paddle 14 is shown assembled to drive-shaft 11. Upon initiation of the drive motor in a rotative, clockwise direction (arrow 25), the paddle 14 is caused to experience a reactive, inertial, counterclockwise force, as shown by the arrow 27. This inertial force is, in part, due to the load imparted to the blade 15 by the dough that is going to be kneaded in the bucket 10. The paddle 14 will shift approximately 25 degrees with respect to shaft 11. This shifting of the paddle 14 about the drive-shaft 11 is made possible by the internally loose fit of the shaft 11 within the bore 18 of the hollow-centre, hub portion 16. Referring again to Figures 2 and 3, the rotative drive-shaft 11 is shown to have a lip or abutment means 28. When the shaft 11 is initially actuated, and the blade 15 experiences the reactive force 27, the lip 28 is caused to rotate over the top face 19 of the hollow-centre, hub portion 16 of the paddle 14. The result is that the abutting edges 30 and 31, respectively, of the lip 28 will ride over the rectangular edges 29 of the bore 18, and engage the top face 19 at points A and B, respectively, as illustrated in Figure 4. The top face 19 will mutually engage with the respective, abutting edges 30 and 31; these abutting surfaces will, therefore, interlock with each other, which causes the paddle 14 to become vertically affixed to the drive-shaft 11. Thus, when the bread is lifted from the bucket 10 after the baking cycle, the paddle 14 will remain in the bucket 10, and not leave with the baked bread.

Claims: A kneading mechanism for making bread, comprising a bucket (10) for receiving bread dough to be kneaded and baked and a rotatable drive shaft (11) disposed in said bucket for rotating a kneading paddle (14) to knead said bread dough, the drive shaft (11) having a base (20) and abutment means (28) thereon and the kneading paddle (14) having a kneading blade (15) extending from a hub (16) having a top face and a second base (23) and a bore (18) therein for attaching the kneading paddle (14) to the drive shaft (11), the bore (18) loosely fitting about the drive shaft (11) and being configured so that when the drive shaft (11) is initially actuated, the shaft will shift with respect to the bore (18) under a reactive force, thereby causing the abutment means (28) thereon to ride over and engage with the paddle (14) to vertically fix the paddle (14) to the drive shaft (11) characterised in that when the kneading paddle (14) is attached to the drive shaft (11) the base (23) of the kneading paddle (14) rests upon the base (20) of the drive shaft (11), the drive shaft having a portion which protrudes beyond the top face of the hub (16) and wherein the abutment means comprises a lip on said protruding portion of the drive shaft (11) which engages with the top face (19) when the drive shaft (11) is initially actuated. A kneading mechanism for making bread, as claimed in claim 1 characterised in that the drive shaft (11) is generally rectangular in cross section and the bore (18) comprises a generally rectangularly-shaped, cross-sectional hole, the bore loosely fitting about the drive shaft (11), so that when said drive shaft is initially actuated, the kneading paddle (14) will be caused to shift with respect thereto whereby the drive shaft will shift approximately 25° with respect to the bore (18) so that the lip (28) will engage with the top face of the paddle (14) when the drive shaft (11) is initially actuated.

Inventors: KUNAVONGVORAKUL KUMKIT, SHAM JOHN CHUN KUEN, KUNAVONGVORAKUL, KUMKIT, SHAM, JOHN CHUN KUEN
Applicants: WING SHING PRODUCTS BVI CO LTD, WING SHING PRODUCTS (BVI) CO. LTD.
Application year: 1998
Main classification: A21B7
IPC codes: B01F7, B01F15, A21B7