US1624274A - Doweling machine - Google Patents

Description

April 12, 1927. 1,624,274

J. M. MYRDAL DOWELING MACHINE Filed Feb. 25, 1926 JM Myrdal Patented Apr. 12, 1927.

JOHN M. MYRDAL, OF TRAIL, ONTARIO, CANADA.

DOWELING MACHINE.

Application filed February 25, 1926.

This invention relates to means for forming dowels and the sockets or recesses in which the dowels are to be fitted, the object of the invention being to provide simple and inexpensive means which will operate efficiently to produce true cylindrical dowels or pins and to form recesses or sockets of proper diameter to snugly receive and fit the dowels. The invention is illustrated in the accompanying drawing and consists in certain novel features which will be partioularly pointed-out in the appended claims.

In the drawing:

Figure 1 is a plan view of my improved doweling device arranged to form the dowel ms; 7 p Fig. 2 is a vertical longitudinal section on the line 22 of Fig. 1;

Fig. 3 is an enlarged elevation of the dowel-forming bit;

Fig. 4 is a similar view of the auger or bit employed to form the dowel-receiving sockets; v

Fig. 5 is a detail perspective view of a guide for the bits, and

Fig. 6 is a detail section on the line 66 of Fig. 2.

In the drawing, the reference-numeral 1 indicates a table or base block l'iav-ing a tran verse vertical shoulder 2 upon its upper surface and adapted toreceive at said shoulder the block 3 from and on which the dowels are to be formed. The base or table 1 is of proper formation to permit the work or block 3 to be secured thereon by a clamp 4% of a well-known type commonly used by carpenters and woodworkers. The base or table 1 has openings 5 formed vertically there through and through these openings are fitted set bolts 6 which are equipped below the table with washers 7 and wing nuts 8.- The upper ends of these bolts arefixed in the base plate 9 of a guiding and supporting member, and mounted upon the bolts immediately below the said base plate are se-- curing disks 10' which are adapted to seat in recesses provided therefor in the upper surface of the base block 1 and have threaded engagement with the respective bolts, washers 11 being fitted between the disks and the bases of the recesses in which they fit so as to receive the thrust of the disks and provide a firm clamping surface. It will be understood that by releasing the wing nuts 8, the bolts may be shifted to a higher position relative to the base block 1, and if the disks 10 be then ro- Serial No. 90,664.

. to be formed.

The guiding and supporting member, of which the plate 9 is the bottom, is constructed of metal and its inner end bears against the shoulder 2. At said end of the plate is an upstanding guiding and bracing plate 12 which presents a true vertical surface to the shoulder 2 and to the block 3. An opening 18 is formed through this upright member 12 and at the outer end of the 1 plate 9 is a shorter foot or vertical guiding plate 14 having an opening 15 therethrough alined axially with the opening 18, as shown most clearly in Fig. 2. These openings 13 and '15 receive and guide the dowel-forming bit which comprises a cutter head 16 and a shank 17 having an outer extremity which is tapered and fiat-sided, as shown at 18, whereby it may be engaged in a suitable I turning tool. In Fig. 1,1 have illustrated,

at 19, a portion of an ordinary carpenters brace which may be easily engaged with the terminal 18 so as to rotatethe bit. The cutter' head 16 is constructed with external obliquely disposed or spiral ribs 20 terminating in teeth 21 which are adapted to cut through the block or body 8 and are preferably somewhat curved, as shown in Fig 3, so as to aid in holding the bit to a rectilinear path as it advances in the body, the spiral ribs 20 serving to remove from the opening all shavings which may be formed. The entire bit is hollow, as shown most clearly in Fig. 2, and the external diameter of the shank immediately in rear of the cutter head is less than the succeeding portion of the shank, as indicated at 22, whereby clearance inserted through the bore 2 1 to push out the broken pin. The shank is provided adjacent its outer end portion with graduations 25 indicating measures of length which cooperate with the vertical post or supporting plate 14 to furnish visual notice of the length of pin which has been formed. The user of the tool will thus obviously be enabled to carry the pin forming operation to any desired extent.

In the use of the tool thus far described. the block 3 is clamped in the position indicated in Figs. 1 and 2 bearing against the inner face of the upright plate 12 and the bit is fitted through the openings 15 and 13 so as to bear against the'presented edge of the body or block 3, as shown in Fig. 2. Rotation of the bit will then cause it to cut into and through the block forming a circle therein and leaving a solid core at the center of the circle. To attain accuracy in the spacing of the dowels and the sockets, the inner face of the upright guide 12 is preferably provided with graduations representing inches and fractions of an inch but I have deemed illustration thereof unnecessary as they arewell-known.

The width of the circular spaces or cuts around the several dowels will obviously be determined by the width of the cutting teeth 21, and usually the dowels are so spaced that the circular cuts overlap or intersect be tween the dowels. Then the waste portions left on the block at the sides of the dowels may be easily removed by the use of a saw.

The openings 13 and 15 will usually serve to efficiently guide the tool and hold it to a rectilinear path but it sometimes happens that the grain of the body 3 or some other qualities inherent therein tend to divert the bit from a true straight path. In such event, the auxiliary guide plates 26 may be em ployed. These guide plates bear against the outer face of the upright 12 and are provided at their centers with openings 27 adapted to aline axially with the opening 13. One end of each plate maybe turned outwardly, as shown at 28, to serve as a handle or finger piece to facilitate its placement and adjacent both ends of both plates there are slots 29 through which set bolts 30 are inserted to engage in the upright guiding member 12 so as to secure the plates firmly in place. The slots 29 will permit the plates to be relatively adjusted and this adjustment will permit the opposed edges of the openings 27 in the plates to be brought into engagement with the shank of the bit so that it will be properly guided in its operation.

To form the openings or sockets in which the dowels are fitted, I provide a bit con sisting of an anger 31 and a shank 32 inscribed with graduations 33, corresponding to the graduations 25 previously mentioned. The external diameter of the auger 31 is the same as the internal diameter of the hollow cutter head 16 so that the opening produced by the use of the auger will snugly receive and hold the dowel. After the dowels have been produced, the body 3 is removed from the table and the member in which the dowels are to be fitted is substituted therefor. The dowel-forming bit is also withdrawn and the auger 31 is substituted therefor to form sockets in said mating member. Of course, the opening13 provided for the cutter head 16 is too large to guide the auger 31 properly and I, therefore, provide the additional guide shown in Fig 5 which consists of a plate 34: adapted to be secured to the outer face of the supporting guide 12 and extend across the opening 13 therein. This plate 3 1 has an opening formed through it at its center to aline axially with the opening 13 and formed on said plate is a sleeve or bushing 35, one end of which will fit within the opening 13. When the auger 31 is engaged within the sleeve or bushing 35, it will obviously be held to a rectilinear path and true sockets will be formed in the work.

It will be understood that doweling bits of various diameters may be employed and guide or bushing plates 3 1 may be used to properly aline the bits in the opening 13 just as the auger 31 is alined therein.

It may sometimes be found advantageous to employ an abutment clip or stop member 37 removably engaged in a groove 36 in the shank of the bit to bear against the guiding support 14 and receive the initial back thrust of the bit.

From the foregoing description, taken in connection with the accompanying drawing, it will be seen that I have provided a very simple mechanism, by the use of which the operation of forming dowels and sockets to receive the same will be very expeditiously and efficiently performed. 1

Having thus described the invention, I claim:

1. A doweling mechanism comprising a support for a body from which dowels are to be formed, a base plate mounted upon said support and having upright members at its ends, said members being provided with axially alined openings therethrough and one of said members being arranged to bear against the body from which dowels are to be formed, and a hollow bit fitted through and supported and guided by the openings in said upright members. 7

2. A doweling mechanism comprising a support, a base plate mounted upon said support and vertically adjustable thereon, upright members at the ends of said base plate having openings formed therethrough, a bit fitted through and guided by said openings, and auxiliary plates adjustably secured to the outer face of the inner upright member and provided at their centers with openings alined axially with the openings in said inner upright member and adapted to have their edges brought into overlapping relation whereby to support the bit.

3. A doweling mechanism comprising a support for a block from which dowels are to be formed, set bolts fitted Vertically through the said support, securing elements having threaded engagement with the bolts to engage the upper and lower portions of the said support, a base plate carried by the upper ends of the set bolts, guides at the ends of the base plate, and a hollow bit fitted through said guides.

In testimony whereof I affix my signature.

JOHN M. MYRDAL. [L. s.]

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