GB1599054A - Machining aid - Google Patents

Description

(54) IMPROVED MACHINING AID (71) We, H. P. BOWMAN ENGINEER ING (LIVINGSTON) LIMITED, a British Company of Grange Road, Houston Industrial Estate, Livingston, West Lothian, Scotland, do hereby declare the invention, for which we pray that a Patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following Statement: This invention relates to an improved machining aid which has particular reference to supporting a work piece on a milling machine, a grinding machine, or some other machine tool having a flat work table, and to a method of machining.

Parallel slips are used for many different machining operations on flat work tables, each such slip being a right parallelepipedic block accurately machined square and flat on its faces (normally on all six faces but optionally only on the four largest faces) usually to a convenient size in Imperial or Metric units.

The invention relates to a modified parallel slip that can be used in novel ways to clamp a work piece for machining.

According to the invention a machining aid comprises a block of tool steel or other hard metal having two pairs of parallel faces, the faces of one pair being at right angles to the faces of the other pair, an inverted slot indenting one face of one pair and opening to at least one end of the block and at least one elongate passage communicating between the other face of said one pair and the recess of the T-slot.

Throughout this specification the term "throat" will be used to define the part of the T-slot which extends normal to but opens into said one face of said one pair and the term "recess" will be used to define the part of the T-slot which is furthest from said one face and which extends parallel thereto.

Preferably the elongate passage communicating with the recess in the slot is a further slot disposed centrally of the width of said other face of the block which further slot breaks into the recess of the T-slot throughout a major part of its length.

The block can be of any convenient size but conveniently lengths of the order of 6 to 9 inches (say 15 to 25 cms.), a width of some 11 inches (say 4 cms.) and a height of some 1 or 141 inches (say 3 cms.) would be typical and a single mverted T-slot would preferably be provided in one of the largest faces of the block centrally of its width and extending throughout the entire length of the block.

The invention will now be further described, by way of example, with reference to the drawings accompanying the provisional specification, in which: Figure 1 is a perspective view of a machine aid in accordance with the invention, Figure 2 is a transverse section through a central region of the aid shown in Figure 1, Figures 3 and 4 show two different methods of using the aid shown in Figure 1 for mounting work pieces on the work table of a milling or grinding machine, and Figure 5 shows how an aid as shown in Figure 1 can be mounted skewise on the work table of a machine tool.

The aid shown in Figure 1 can be used as a conventional parallel slip, faces 1 and 2 being accurately flat and parallel one to the other and at right angles to faces 3 and 4 and also to end faces 5 and 6. The block can be formed from any convenient hard metal (e.g. tool steel) and differs from the conventional parallel slip in having an inverted T-slot indenting the face 1 and extending throughout the entire length of the block.

The throat 7 of the T-slot is disposed centrally of the face 1 and the recess 8 of the slot extends down to approximately half the height of the block. An elongate slot 9 is disposed centrally in the face 2 of the block and extends almost the entire length of the block, the slot 9 breaking into the recess 8 throughout its length.

The aid shown in Figures 1 and 2 can be secured to a flat work table by means of bolts passing through the slot 9 and tightened into nuts located in the recess of the T-slot in the work table. This forces the face 2 of the aid against the flat surface of the work table holding the aid in any desired position on the work table. By using an elongate slot 9, the aid can be disposed at any convenient angle to the T-slots in the work table as can be seen in Figure 5. The bolts securing the aid to the work table 10 are indicated at 11 in Figure 5.

If it is wished that the-bolts 11 do not obstruct the cross-section of the T-slot in the block, a hollow (shown dotted at 12 in Figure 2) can be provided in the base of the recess 8 to accommodate the bolt head.

Figure 3 shows how four aids as shown in Figure 1 can be used to secure a flat sheet 13 above the work table 14 of a machine tool.

The four aids are clamped to the work table by means of bolts located in the slots 9 and the work piece 13 rests on the flat faces 1 of the four aids. Clamping of the work piece is effected by any conventional work piece clamp 15 located in or above a T-slot. One form of clamp which is particularly suitable for use with the aid shown in Figure 1 is a clamp as described in the specification of U.K. Patent No. 1430762.

Figure 4 shows how two aids can be used to support a work piece 16 above the work table 17 of a machine tool. The opposite ends of the work piece shown in Figure 4 are engaged by clamps 18 which are adjustably located in suitable T-slots of the work table 17. Between these clamps 18 two aids in accordance with the invention are securely mounted on the work table these running below the work piece 16 as shown at 19 in Figure 4. In the T-slot of each aid 19 is located further work piece clamps 20, these being tightened against the sides of the work piece 16 to firmly hold it down on to the upper face of the aids 19. The two clamps 20 on the opposite side of the work piece 16 are not shown in Figure 4.

WHAT WE CLAIM IS: 1. A machining aid comprising a block of tool steel or other hard metal having two pairs of parallel faces, the faces of one pair being at right angles to the faces of the other pair, an inverted T-slot indenting one face of one pair and opening to at least one end of the block and at least one elongate passage communicating between the other face of said one pair and the "recess" (as hereinbefore defined) of the T-slot.

2. A machining aid as claimed in claim 1, in which the elongate passage communicating with the "recess" in the T-slot is a further slot disposed centrally of the width of said other face of the block.

3. A machining aid as claimed in any preceding claim in which the block has a length of 15 to 25 cms and a rectangular cross-section normal to its length, a single inverted T-slot is provided in one of the largest faces of the block centrally of its width and extending throughout the entire length of the block.

4. A machining aid as claimed in any preceding claim, in which the "recess" of the T-slot extends down to substantially half the thickness of the block measured between said one and said other faces of the block.

5. A machining aid as claimed in any preceding claim, in which the passage breaks into the "recess" of the T-slot substantially throughout the length of the T-slot.

6. A machining aid as claimed in any preceding claim, in which the passage terminates in an enlarged hollow which communicates with the "recess" of the T-slot.

7. A machining aid substantially as hereinbefore described with reference to, and as illustrated in Figures 1 and 2 of the drawings accompanying the provisional specification.

8. A method of machining a work piece using at least two aids as claimed in claim 1, in which the aids are clamped, via their passages, to the work table of a machine tool in spaced-apart relationship with their said one faces uppermost, the work piece is rested on the said one faces and is clamped thereagainst by a work piece clamp located in the T-slot of each aid.

9. A method of machining a work piece substantially as hereinbefore described with reference to, and as illustrated in Figures 3 and 4 of the drawings accompanying the provisional specification.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. position on the work table. By using an elongate slot 9, the aid can be disposed at any convenient angle to the T-slots in the work table as can be seen in Figure 5. The bolts securing the aid to the work table 10 are indicated at 11 in Figure 5. If it is wished that the-bolts 11 do not obstruct the cross-section of the T-slot in the block, a hollow (shown dotted at 12 in Figure 2) can be provided in the base of the recess 8 to accommodate the bolt head. Figure 3 shows how four aids as shown in Figure 1 can be used to secure a flat sheet 13 above the work table 14 of a machine tool. The four aids are clamped to the work table by means of bolts located in the slots 9 and the work piece 13 rests on the flat faces 1 of the four aids. Clamping of the work piece is effected by any conventional work piece clamp 15 located in or above a T-slot. One form of clamp which is particularly suitable for use with the aid shown in Figure 1 is a clamp as described in the specification of U.K. Patent No. 1430762. Figure 4 shows how two aids can be used to support a work piece 16 above the work table 17 of a machine tool. The opposite ends of the work piece shown in Figure 4 are engaged by clamps 18 which are adjustably located in suitable T-slots of the work table 17. Between these clamps 18 two aids in accordance with the invention are securely mounted on the work table these running below the work piece 16 as shown at 19 in Figure 4. In the T-slot of each aid 19 is located further work piece clamps 20, these being tightened against the sides of the work piece 16 to firmly hold it down on to the upper face of the aids 19. The two clamps 20 on the opposite side of the work piece 16 are not shown in Figure 4. WHAT WE CLAIM IS:

1. A machining aid comprising a block of tool steel or other hard metal having two pairs of parallel faces, the faces of one pair being at right angles to the faces of the other pair, an inverted T-slot indenting one face of one pair and opening to at least one end of the block and at least one elongate passage communicating between the other face of said one pair and the "recess" (as hereinbefore defined) of the T-slot.

2. A machining aid as claimed in claim 1, in which the elongate passage communicating with the "recess" in the T-slot is a further slot disposed centrally of the width of said other face of the block.

3. A machining aid as claimed in any preceding claim in which the block has a length of 15 to 25 cms and a rectangular cross-section normal to its length, a single inverted T-slot is provided in one of the largest faces of the block centrally of its width and extending throughout the entire length of the block.

4. A machining aid as claimed in any preceding claim, in which the "recess" of the T-slot extends down to substantially half the thickness of the block measured between said one and said other faces of the block.

5. A machining aid as claimed in any preceding claim, in which the passage breaks into the "recess" of the T-slot substantially throughout the length of the T-slot.

6. A machining aid as claimed in any preceding claim, in which the passage terminates in an enlarged hollow which communicates with the "recess" of the T-slot.

7. A machining aid substantially as hereinbefore described with reference to, and as illustrated in Figures 1 and 2 of the drawings accompanying the provisional specification.

8. A method of machining a work piece using at least two aids as claimed in claim 1, in which the aids are clamped, via their passages, to the work table of a machine tool in spaced-apart relationship with their said one faces uppermost, the work piece is rested on the said one faces and is clamped thereagainst by a work piece clamp located in the T-slot of each aid.

9. A method of machining a work piece substantially as hereinbefore described with reference to, and as illustrated in Figures 3 and 4 of the drawings accompanying the provisional specification.