GB2180185A - Woodworking plane - Google Patents

Abstract

A plane comprises a body (1) having a sole plate (2) and a blade (5) projecting through an opening in the sole plate. At each side of the plane there is a support bar (7) to which a skid (8) is connected by a parallelogram linkage (9 to 14). The lower surface of each skid lies in a plane parallel to the plane of the sole plate so that the plane may be used to thickness a work piece to a thickness equal to the perpendicular distance between the plane of the sole plate and the plane of the lower surfaces of the skids.

Description

SPECIFICATION Improvements relating to planes This invention relatesto planesfor use in woodworking.

Woodworking planesofvarioustypesarewell known. For example, the conventional hand-held plane comprises a body having a sole plate with an opening therein, and a cutter blade adjustably mounted on the body with its cutting edge projecting through the opening in the sole plate. Forward move mentofthe plane results in the blade cutting and smoothing the surface of the work piece. Electric planes are also known, which similarly comprise a body having a sole plate comprising an infeedtable and an outfeed table with an opening therebetween.

A rotary cutter driven by an electric motor has a cutting section projecting through the opening. The plane is still moved to and fro by hand, but the drive to the cutter is from the motor rather than relying on manual effort. The infeed table may be adjusted to alter the depth of cut.

Both the hand-held and the electric plane are effective and efficient tools in smoothing the surface of a work piece. However, there is also a requirement forthicknessing planes, that isto say tools capable of uniformly cutting an elongated work piece to a required thickness, either across the whole surface ofthe work piece or in a predetermined band of the work piece. The only effective types ofthicknessing plane currently in use are large and expensive powerdriven piecesofequipmentdedicatedtothatpart- icularfunction. It would be of advantage if the conventional small hand or electric plane was ableto perform a thicknessing operation, and the invention seeks to provide a plane which will perform such function.

According to the invention a plane comprises a body having a sole plate, a cutter mounted on the body and projecting through an opening in the sole plate, and two skids spaced apart transversely of the sole plate, each skid having a support surface lying in a plane parallel to the plane of the sole plate.

A plane in accordance with the invention may thus be used to thickness a work piece so that the finished work piece has a thickness equal to the perpendicular distance between the plane of the cutting part ofthe blade and the plane ofthe skids. If the skids are coplanarthentheworkpiecewill befinished in a plane parallel to the plane of a support on which the skids rest; if the skids are not co-planarthen the work piece may be finished to a plane lying at an angle to the plane of such support. Thus, the plane according to the invention may be produced to give any desired result.

Preferably each skid is adjustable relative to the sole plate in orderto adjust the perpendiculardistance between the plane of the sole plate and the plane ofthe support surface of the respective skid. By calibrating the adjustment of the skids thicknessing to required dimensions may readily be achieved.

In one embodiment of the invention the skids may be mounted at opposite sides of the body, whereas in an alternative embodiment the skids may be mounted apart at the same side of the body, being can tilevered outfrom the body. Thefirstembodiment readily allows thicknessing of a work piece lying between the skids, whereas the second embodiment allowsthicknessing of a work piece lying to that side of one skid which is opposite to the side on which the other skid lies. In this latterembodimentthicknessing or rebating of a section only of a work piece may be effected.

Conveniently each skid is mounted on the body by way of a parallelogram guide system that ensures thatinall positionsofadjustmenttheplaneofthe skid is parallel to the plane of the sole plate. Asimple method of mounting each skid is to mount it on a support bar secured to the body, and if a parallelogram guide system is used that may then extend between the support bar and the skid. Adjustment may then simply be effected by an adjusting screw operating between the support bar and the skid. Such screw may be calibrated, preferably with direct calibration to indicate work piece thickness, and may suitably be of the micrometer type threaded in the support bar and having an enlarged head that is rotatable relative to, and captive in, a groove formed in the upper surface of the skid.

Each support bar may be directly secured to the body ofthe plane, or may be secured to one or more rods orotherguides extending from the body. In the lattercasetherodsorguides may be adjustableso that skids may be fitted thereto either to lie one to each side of the body or both to lie to the same side of the body.

In orderthatthe invention may be betterunderstood specific embodiments of planes in accordance therewith will now be described in more detail, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a side elevation of a hand plane according to the invention; Figure2 is an enlarged view of part ofthe plane of Figure 1; Figure 3 is a section on the line Ill-Ill of Figure 2; Figure 4 is a side elevation of an electric plane according to the invention; Figure5is a plan ofthe plane of Figure 4; and Figures 6and 7show alternative ways in which the plane of Figures 4 and 5 may be employed.

Referring nowto Figure 1 there is shown a plane having a body 1 with a sole plate 2 and forward and rear handles 3 and 4. A blade 5 is mounted on the plane and projectsthrough an opening (notshown) in the sole plate in conventional manner. The blade 5 may be secured relative to the body in any manner suitablefora hand plane, for example byan adjusting screw 6.

At each side of the body of the plane there is secured a support bar7 and each support bar has associated therewith a skid 8. Two angled guides 9 and 10 which lie parallel to one another have internal slots which engage pins 11 and 12 on the support bar and pins 13 and 14 on the skid. The pins, guides, support bars and skids form a parallelogram linkage. The lowersurfaceofthesupportbarandthe upperand lower surface of the skids each lie parallel to the plane ofthe sole plate 2, and the parallelogram lin kage thus constrains each skid to move so that its lower surface always retains its parallel relationship to the sole plate.The perpendicular distance between the sole plate and the support bar, and thus the perpendicular distance between the lower surface of the skid and the sole plate may be adjusted by a micrometer screw 15 extending through a correspondinglythreaded bore 15a in the supportsurface. The lower end of the screw has a frusto-conical head 16 which is received in afrusto-conical groove 17 formed in the upper surface ofthe skid 8. Rotation of thescrewwillthusmovetheskidupwardlyordown- wardly relative to the support bar and thus to the sole plate, the skid being retained in its parallel relation shinto the sole plate. An enlarged section 18 at one end ofthe guide 17 allows assembly ofthe parts.The screw 15 is suitably calibrated on a scale that represents the distance between the sole plate and the lower surface oftheskid.

The assembly of the skids at the two sides ofthe plane is identical. Accordingly, it will readily be seen from the Figures that if the two skids are set at ident icalsettingstheymayrunona plane surface andwill supportthesole plate parallel to that surface and ata predetermined distance above that surface.If a work piece is now supported on that surface between the skids the plane may be operated so that the bladewill cut material from the exposed surface ofthework piece and will eventually smooth and thickness the work piece so that it has a substantially uniform thickness equal to the perpendicular distance between the plane of the sole plate and the plane ofthe lowersurfaces oftheskids.Averyaccurate result may be obtained. If the skids are adjusted to different distances from the sole plate it will then be seen that the blade will lie atan angle to the supportsurface, and a work piece may then be finished to a required angle and thickness.

Figure 4 illustrates an electric plane similartothat shown in Figure 1, wherein the blade is replaced bya rotatable cutter 20 driven by a suitable electric motor.

The cutter 20 is mounted for rotation on the plane body 21 and forward and rearward handles 22 and 23 are provided in known manner. The rotary cutter projects below an infeed table 24a to the level of an outfeed table 24b, the two tables together forming a sole plate. In this embodiment the plane body has two transversely extending bores such as 25 therein through which pass respective rods 26 and 27, the rods projecting to each side ofthe body. At each end, each of the rods is secured to a support bar, 28,29 respectively. The connection between the rods and support bar may be a releasable and adjustable connection sothatthe support bars may be adjusted in their lateral position relative to the body of the plane, orthe connection may be a fixed connection.Each support bar has an associated skid 30,31 respectively connected to the support bar by a parallelogram linkage incorporating guides such as 32,33 similar to the guides 9, 10 shown in Figure 1. Each skid may thus be adjusted relative to its respective support bar, while maintaining a parallel relationship between the lower surface of the skid and the sole plate ofthe plane. An adjusting screw 34, preferably a calibrated micrometer screw is provided between the support bar and the respective skid for effecting this adjustment. Figure 6 shows one way in which the plane of Figures 4 and 5 may be used to thickness a work piece 35 located between the skids 30 and 31.

The skids rest on a support surface 36 which also supports the work piece and use of the plane until the skids both run flat on the surface of the support 36 will cause the cutter 20 to cut the work piece to a presetthickness equal to the perpendicular spacing between the plane of the cutting part of the blade and the plane of the lower surfaces of the skids.

Figure 7 shows an alternative use with the rods 26 and 27 mounted oradjustedto lie principally to one side of the body 21 of the plane, with both skids 30 and 31 lying to the same side of the plane. The plane may thus work along one edge only of the work piece 35 supported on the surface 36 in orderto rebate a section of the work piece to a thickness equal to the perpendicular distance between the sole plate and the plane of the lower surfaces of the skids.

The skids on the planes shown in the Figures have rounded leading edges in orderthatthey may clear the stop that is conventionally provided for the work piece to rest against. It will be appreciated, however, that this is not essential . Itwill also be understood that many modifications may be made to the planes shown in the drawings, and that the method of skid mounting described is only one of many methods that may be used. For example, in one simple emb odimentthe lower surfaces of the skids may project inwardly beneath the sole plate and the skids may be connected to the body by simple screws which may be released and tightened at will.Setting to a desired thickness may then readily be achieved by inserting a uniformthicknessshim betweentheskidandthe sole plate and securing the skid to the body with the shim firmly clamped in position. If calibrated adjusting means on the plane body are required, then these may be provided in ways other than the simple mic rometer screw described, and additionally the guide systemformaintainingthelowersurfacesofthe skids parallel to the sole plate may be modifiedfrom that shown. It will further be understood that the invention may be applied to any type of hand plane or small electric plane and those shown are merely illustrative.

It is also possible to modify an existing plane by mounting it securely in a cradle that is provided with skids similarto those described herein. The cradle skids may be adjustable relative to the cradle body by a parallelogram linkageorbyanyothersuitableadju- stment system.

Claims (8)

1. A plane comprising a body having a sole plate, a cutter mounted in the body and projecting through an opening in the sole plate, and two skids spaced apart transversely of the sole plate, each skid having a supportsurface lying in a plane parallel to the plane of the sole plate.

2. A plane according to claim 1 in which each skid is adjustable relative to the sole plane in orderto adjust the perpendicular distance between the plane of the sole plate and the plane of the supportsurface.

3. A plane according to claim 1 or 2 in which each skid is mounted on the body byway of a parallelogram guide system.

4. A plane according to claim 3 in which the parallelogram guide system extends between the skid and a support bar secured to the body.

5. A plane according to claim 4 in which adjustment may be effected by an adjusting screw operating between each skid and its respective support bar.

6. A plane according to claim 4 or claim 5 in which each support bar is secured directly to the body.

7. A plane according to claim 4 or claim 5 in which each support bar is a rod extending through the body and adjustable transversely of the body.

8. A plane substantially as described with referpence to Figures 1 to 3 or Figures 4 and 5 of the accompanying drawings.