CN-121989064-A - Workpiece holding device

CN121989064ACN 121989064 ACN121989064 ACN 121989064ACN-121989064-A

Abstract

A workpiece holding device for detachably attaching a workpiece to the device. The workpiece may be provided with elongate wedge-shaped channels along both sides thereof and with indexing holes in the bottom surface thereof. The workpiece holding device has a body with one or more open slots for receiving a clamp assembly and with first and second cavities configured to receive spring-biased locating pins. The cross-section of the one or more open slots may have a rounded polygonal shape. The clamp assembly has first and second wedge-shaped portions that engage the channels of the workpiece sides to hold the workpiece in place during a machining operation. The materials and construction of the workpiece clamping device provide strength, stability and accurate positioning to optimize machining operations and reduce errors and wastage.

Inventors

Brian Fangda
Daniel. M. Robinson

Assignees

布林克曼产品公司

Dates

Publication Date: 20260508
Application Date: 20251106
Priority Date: 20241106

Claims (20)

1. A workpiece holding device for removably attaching a workpiece having an elongated wedge channel along both sides thereof and at least one indexing aperture in a bottom surface thereof, the workpiece holding device comprising: A body having a proximal end, a distal end, and a mounting surface disposed therebetween, the body including at least one elongated opening extending transversely through the body and having a portion intersecting the mounting surface to define at least one open slot in the mounting surface, and at least one dowel hole adjacent a cavity in the body configured to receive a dowel pin having a first end and a second end disposed opposite the first end, the first end of the dowel pin being sized for slidable insertion into the at least one indexing hole of the workpiece; a biasing member disposed in the cavity and configured to bias the locating pin in an upward direction; at least one clamp assembly insertable into the at least one elongated opening and configured to engage the wedge-shaped channel in the workpiece.
2. The workpiece holding device of claim 1, wherein the clamp assembly further comprises a clamp bar having a main body and a large head, the main body having threads along a portion of its length, the large head having means for rotating the bar, a first clamp block having a threaded bore configured to engage threads on the clamp bar and a first wedge portion protruding through the open slot when the clamp assembly is inserted into the at least one elongated opening, a second clamp block having an opening configured to receive the main body of the clamp bar slidably therethrough and a second wedge portion engaged with the second clamp block around the opening, the second wedge portion protruding through the open slot when the clamp assembly is inserted into the at least one elongated opening, and a second spring disposed around the clamp bar between the first clamp block and a spacer portion, a third spring disposed around the clamp bar between the clamp block and the second clamp block.
3. The workpiece holding device of claim 1, further comprising a platform extending above the mounting surface.
4. A workpiece holding device according to claim 3, wherein the workpiece is engaged with the mounting surface and the platform when the workpiece is mounted on the workpiece holding device.
5. The workpiece holding device of claim 1, further comprising a tie bar extending across a portion of the at least one open slot in the mounting surface.
6. The workpiece holding device of claim 1, wherein the biasing member is a coil spring.
7. The workpiece holding device of claim 1, wherein the body is composed of cast iron.
8. The workpiece holding device of claim 1, wherein at least a portion of the at least one elongated opening is shaped to include a rounded triangle form.
9. The workpiece holding device of claim 1, wherein the at least one dowel hole comprises a plurality of dowel holes having different diameters or shapes.
10. The workpiece holding device of claim 1, wherein the means for rotating the lever comprises a hexagonal opening in the head of the clamp lever.
11. The workpiece holding device of claim 1, further comprising a wall defining the cavity, the wall having a groove defined therein for receiving a retaining ring to prevent the dowel from exiting the cavity.
12. A workpiece holding device for removably attaching a workpiece having an elongated wedge channel along both sides thereof and at least one indexing aperture in a bottom surface thereof, the workpiece holding device comprising: A body having a proximal end, a distal end, and a mounting surface disposed therebetween, the body including at least one elongated opening extending transversely through the body and having a portion intersecting the mounting surface to define at least one open slot in the mounting surface, and at least one dowel hole adjacent a cavity in the body configured to receive a dowel pin having a first end and a second end disposed opposite the first end, the dowel pin having a shoulder defined between the first end and the second end, the first end of the dowel pin sized for slidable insertion into the at least one indexing hole of the workpiece; One or more platforms extending above the mounting surface; One or more tie bars extending across a plurality of open slots in the mounting surface; a biasing member disposed in the cavity and configured to bias the locating pin in an upward direction; A retaining ring disposed in the cavity and configured to engage a shoulder on the dowel to prevent the dowel from exiting the cavity; at least one clamp assembly insertable into the at least one elongated opening and configured to engage a wedge-shaped channel in the workpiece, and Wherein the cross-section of the at least one elongated opening comprises a rounded polygonal shape.
13. The workpiece holding device of claim 12, wherein the clamp assembly includes a clamp bar having a main body and a large head, the main body having threads along a portion of its length, the large head having means for rotating the bar, a first clamp block having a threaded bore configured to engage threads on the clamp bar and a first wedge portion protruding through the open slot when the clamp assembly is inserted into one of the openings, a second clamp block having an opening configured to receive the main body of the clamp bar slidably therethrough and a second wedge portion protruding through the opening when the clamp assembly is inserted into the at least one elongated opening, and a first spring disposed around the clamp bar between the first clamp block and the divider portion, a second spring disposed around the clamp bar between the divider portion and the second clamp block.
14. The workpiece holding device of claim 13, wherein the workpiece is engaged with the mounting surface and the platform when the workpiece is mounted on the workpiece holding device.
15. The workpiece holding device of claim 13, wherein the first spring and the second spring are coil springs.
16. The workpiece holding device of claim 13, wherein the body is composed of cast iron.
17. The workpiece holding device of claim 13, wherein the at least one dowel hole comprises a plurality of dowel holes having different diameters or shapes.
18. The workpiece holding device of claim 13, wherein the means for rotating the lever comprises a hexagonal opening in the head of the clamp lever.
19. The workpiece holding device of claim 13, wherein a wall defining the cavity has a recess defined therein, the recess configured to receive the clasp.
20. A workpiece holding device for removably attaching a workpiece having an elongated wedge channel along both sides thereof and at least one indexing aperture in a bottom surface thereof, the workpiece holding device comprising: A body having a proximal end, a distal end, and a mounting surface disposed therebetween, the body including one or more elongated openings extending transversely through the body and having a portion intersecting the mounting surface to define one or more open slots in the mounting surface, and one or more dowel holes adjacent a cavity in the body configured to receive a dowel pin having a first end and a second end disposed opposite the first end, the first end of the dowel pin being sized for slidable insertion into the at least one indexing hole of the workpiece; One or more platforms extending above the mounting surface; one or more tie bars extending across the one or more open slots in the mounting surface; means for biasing the locating pin in an upward direction; Means for preventing the dowel from exiting the cavity; a clamping device for clamping the workpiece to the workpiece holding device, the clamping device insertable into the one or more elongated openings and configured to engage a wedge-shaped channel in the workpiece, and Wherein the cross-section of the one or more elongated openings comprises a rounded triangular shape.

Description

Workpiece holding device Technical Field The present invention relates to a workpiece holding device for firmly clamping a workpiece for machining, and more particularly, to a device capable of reliably supporting workpieces of different sizes suitable for use in numerical control machining applications. Background When a raw material or partially manufactured component is to be machined, the workpiece must be reliably clamped to a substrate or other manufacturing platform to stably hold the workpiece in a precise, predictable position so as to be able to resist the forces that the machining operation to be performed generates on the workpiece. Typical machining operations include drilling, boring, honing, lapping and milling. For example, in Computer Numerical Control (CNC) machining, a machine tool such as a milling head is programmed to follow a very precise path. The workpiece must be extremely precisely positioned relative to a CNC machine reference point/plane that is associated with or used to measure the machining path. Many different indexing and clamping systems have been developed to allow positioning of a workpiece at a particular location on a support plate. The gripping device typically has fingers, jaws, a strap, or other means that extend on the side of the workpiece opposite the support surface. While generally effective, the upper surface clamps must be carefully positioned to avoid interfering with movement of the machine tool (e.g., milling head) over the workpiece. The upper surface clamping device also limits access of the cutting tool (e.g., end mill) to a portion of the workpiece. Insufficient clamping pressure or too few clamps are used, which may shift the workpiece during machining, resulting in wasted product, over tolerance, and possible damage to the machine tool. Excessive clamping pressure may directly result in damage to the workpiece or over tolerance in the machining operation due to elastic deformation of the workpiece. In addition, the clamp placement error may cause damage to the clamp, cutting tool, and machine tool. In many workpiece operations, it is desirable to use a workpiece holder equipped with jaws and working surfaces that are at least as wide as the workpiece being machined to ensure that the workpiece is adequately supported during the machining operation. Furthermore, as numerically controlled machine tools are increasingly used, the workpiece must be clamped in a very precise or indexed position on the table in order for the preprogrammed process to produce the desired operation. It is often desirable to provide multiple workpieces to a processing apparatus and to be able to process all surfaces of the workpieces in one operation to reduce the amount of time for machine setup and tool changing. However, because the working surface of the prior art work holding pliers and the width of the jaws cannot be enlarged to accommodate a wider work piece or work pieces, a user may be forced to inventory a plurality of different sized work piece holders. Such workpiece holders typically cost several hundred dollars, and thus, a typical machine owner cannot afford a large inventory of such workpiece holders. It may also be beneficial to be able to remove the workpiece from the clamping apparatus for inspection or other purposes and then to replace it precisely in the same position on the workpiece holder. There remains a need for improved indexing and clamping systems for workpieces to be machined. In particular, there is a need for an improved system that will reliably hold a workpiece without slipping in a manner that makes a large portion of the workpiece surface available for machining operations. Disclosure of Invention The present invention provides a workpiece holding device (10) for removably attaching a workpiece (400) to a mounting surface (22) for machining, wherein the brackets reference corresponding parts, portions or surfaces of the disclosed embodiments for purposes of illustration only and not limitation. The workpiece (400) may be provided with elongated wedge-shaped channels (409) along both sides thereof and at least one indexing hole (415) at the bottom surface (403) thereof. The workpiece holding device (10) includes a body (13), the body (13) having a proximal end (16), a distal end (19), and a mounting surface (22) disposed between the proximal end (16) and the distal end (19). The body (13) includes a plurality of elongated rounded polygonal openings (28) extending transversely therethrough and having portions intersecting the mounting surface (22) to define a plurality of open slots (43) in the mounting surface (23). The body (13) includes tie bars (46) extending across a portion of the open slots (43) and a plurality of registration pin holes (49) extending downwardly into the body (13) between the open slots (43). The dowel bore (49) is configured to receive a spring-biased dowel (52) having a first end (64) and a second end (67) disposed o