SU994264A1 - Device for clamping cut logs - Google Patents

Description

The invention relates to the woodworking industry, in particular, to equipment for the production of peeled veneer. 5

Known clamping cam, made in the form of removable bushings having radially spaced teeth on the working surface in the form of trihedral prisms and fixed on the front, θ of them ends of the spindles of husking machines [1].

Clamping cams of this design do not provide reliable fastening and stable basing of churak. As a result, ’5 churak splits along radial planes with a cutting force c. the process of cutting veneers, especially of increased thickness, and with a decrease in the diameter of the chuck cancer at the end of peeling.

A device for clamping churaks is known, which includes a cylindrical cam with a shank, outer and inner ring sector teeth, and radial teeth mounted in radial grooves [2].

However, with the axial introduction of the teeth of this clamping device into the wood of the splittable churaks, a lot of effort is required from the side of the spindles — 30 weeks, and the modern designs of the I hydraulic cylinders of the husking spindles of the machines do not provide the force sufficient to introduce the teeth to the full depth along the height of their profile. This impairs the reliability of the clamping and basing of churak during peeling, since the contact area of the working surfaces of the teeth with the wood is small. In addition, the basing of churaks with a bevel of cut end sections is not provided, which leads to an increase in the consumption of raw materials. ''

The purpose of the invention is to improve the reliability of the clamp and the accuracy of the base of churaks.

This is achieved by the fact that in the proposed device sector and radial cam teeth are made '. with a variable angle of the inclined face, 'the outer annular sector teeth having a height greater than the inner ones; >

In FIG. 1 shows a clamping cam (longitudinal section); in FIG. 2 - the same, side view A from the side of the teeth; in FIG. 3 - transverse profile of the teeth.

A device for clamping churaks includes a cylindrical cam (sleeve) 1 with a shank 2 at one end, outer 3 and inner 4 sector ring teeth and radial grooves 5, radial teeth 6 are mounted in radial grooves 5 of cam 1 and fixed with screws 7.

The working edges 8 of the outer 3 and inner 4 ring sector teeth are made in the form of circular arcs concentrically located on the end surface of the cam 1, and the inclined edges 9 and 10 of these teeth are facing each other. The inclined faces of all the teeth are made with a variable angle: the angle Q ^ y of the top of the tooth is less than the angle of friction of the material of the cam (steel) on the wood (15 - 17 °), which reduces the effort of introducing the teeth into the wood; the angle to the base of the tooth is greater than the angle of friction (22-25%), which ensures the ease of the teeth coming out of the wood of churak after peeling. Radial teeth 6 have an inclined edge 11 with a variable angle of inclination and H * ₂ · The outer ring teeth have a height h _H greater than the height h _{B of the} inner ring and radial teeth. The excess of the external teeth over the internal ones depends on the size of the allowed bevel cut of the end section and can be determined from,,, С d x ^h - ^h H ^h B “7 d ~ * expressions of the beetroot press creates favorable conditions for the extraction of teeth from wood. After this, the cycle is repeated.

When the device is brought to the end section of a churak with a bevel, the cuts first begin to be introduced into the wood 'along the borders of the annual layers' of the outer teeth 3, which additionally center the churak, eliminating the possibility of its transfer in the presence of a bevel cut on the end sections (i.e. when the end sections not perpendicular to the longitudinal axis of the churak). Then, internal annular sector teeth 4 along the boundaries of the annual layers and radial teeth 6 along the radii of the end sections of the churak are introduced.

The proposed design of the clamping churak provides, in comparison with the known, the following positive effect:

- improves the accuracy of basing churak and improves the quality of veneer due to greater uniformity of thickness;

- decreases the effort of introducing the cam into the wood, 1.2 ... 1.5 times;

- reduced consumption of raw materials for the production of veneer by 6-10%;

- increased productivity; ,

- it is possible to use churaks with a bevel cut on end sections, which expands the raw material base of plywood production.

allowable bevel cut, mm; 35 outer diameter of the clamping cam sleeve, ι ^ ι;

diameter of churak in end section, mm.

in the calculations, we can take d <= 40 and d = 220 mm, then the formula is like h = where C ^d k 'd

When = 110 mm will

The device operates as follows.

In the initial period, vertex tooth sections are introduced into 45 wood with an angle at the apex of% less than the angle of friction. This provides a reduction in the implementation effort with a sufficient depth of implementation. At the end of the introduction of $ q teeth into the wood, its greater compression and deformation occurs due to the introduction of tooth sections with an angle greater than the angle of friction into the wood.

After breaking the churak, the clamping device receives a reverse stroke, and the teeth are disengaged from the churak wood. Moreover, due to increased compression and residual deformation of the wood by the teeth at the end of the

Claims (2)

The invention relates to the woodworking industry, in particular, to equipment for the production of peeled veneer. A clamping cam is known, made in the form of removable sleeves, radially located teeth on the working surface in the form of triangular prisms and fixed at the ends of them by the ends of the spindles of shelling machines 11. Clamping jaws of this design do not provide reliable fixation and stable base of the chorack. churak along radial planes when cutting forces are applied in, the process of cutting veneer, especially increased thicknesses and decreasing the diameter of the churak at the end of peeling. A device for snagging is known, comprising a cylindrical cam with a shank, outer and inner annular sector teeth, and radial teeth mounted in radial grooves 2}. However, the axial insertion of the teeth of this clamping device into the wood of the separated logs requires a lot of effort from the spindles, and the modern designs of 1 hydraulic cylinders of the spindle shelling machines do not provide enough force to insert the teeth to the full depth of their profile. This impairs the reliability of clamping and basing the blockage during peeling, since the contact area of the working surfaces of the teeth with wood is small. In addition, there is no provision for the basement of beads with a bevel that has cut the end sections, which leads to an increase in the consumption of raw materials. The purpose of the invention is to improve the reliability of the clamping and accuracy of the base of the block. This is achieved by the fact that in the proposed device the sector and radial cam teeth are made. with a variable angle of the inclined face, and the outer annular sector teeth have a height greater than the inner; 1 FIG. 1 shows a clamping cam (longitudinal section); in fig. 2 - the same, view A from the side of the teeth; in fig. 3 - transverse tooth profile. The device for clamping clowns includes a cylindrical cam (sleeve) 1 with a shank 2 at one end, outer 3 and inner 4 sectorary annular teeth and radial grooves 5, radial teeth 6 mounted in radial grooves 5 of cam 1 and fixed with screws 7. Working edges 8 the outer 3 and inner 4 annular sector teeth are made in the form of a cam 1 circular arcs located on the end face over the cam post 1, and the inclined faces 9 and 10 of these teeth are facing each other. The inclined edges of all the teeth are variable with a variable angle: the tops of the tooth are smaller than the friction angle of the cam (steel) material on wood (15-17), which ensures a reduction in the efforts to introduce the teeth into the wood; the angle H to the base of the tooth is greater than the friction angle (i22–25%), which makes it easy for the teeth to exit the chorack wood after peeling. The radial teeth 6 have an inclined face 11 with variable inclination angle H and the outer ring teeth have a height h greater than the height hg of the internal annular and radial teeth. The magnitude of the outer teeth over the inner teeth depends on the size of the allowable bevel of the cut cross section and can be determined from the expression - h 2 where C is the allowable cut of the cut, mm outer diameter of the clamping cam sleeve, d is the block diameter in the face section, mm. When calculating, you can take d 110 mm and d 2ZP mm, then the formula will look like h -t- The device works as follows. In the initial period, the tops of teeth with an angle at the apex of H, which is smaller than the friction angle, are introduced into the wood. This provides a reduction in penetration force with a sufficient depth of insertion. At the end of the introduction of the teeth into the wood, it is more compressed and deformed due to the introduction into the wood of the teeth sections with an angle greater than the friction angle. After razlushkvani churaka clamping. the device receives a return stroke, and the teeth are disengaged from the wood of the churak. At the same time, due to the increased compression and residual deformation of the wood by the teeth at the end of the churak clamping, favorable conditions are created for the removal of the teeth from the wood. After that, the cycle is repeated. When the device is brought to the end section of a block with a bevel of a cut, sections are first started to be inserted into the wood along the boundaries of the annual layers of the outer teeth 3, which additionally center the block, eliminating the possibility of its transfer if there is a bevel of the end sections when the end sections are not perpendicular to the longitudinal axis of the block. Then, internal annular sector teeth 4 are introduced along the boundaries of the annual layers and radial teeth 6 along the radii of the end sections of the block block. The proposed clamping block design provides the following positive effect in comparison with the known ones: - the accuracy of the block base is increased and the quality of the veneer is improved due to greater thickness uniformity; - the effort to insert a cam into wood is reduced by 1.2 ... 1.5 times; - the consumption of raw materials for the production of veneer is reduced by 6-10%; - increased performance; , - it is possible to use sawheads with a bevel that has cut the end sections, which expands the raw material base of plywood production. Claims of Invention. Chuck clamping device. comprising a cylindrical cam with a shank, outer and inner annular sector teeth, radia- tion teeth mounted in radial grooves, characterized in that, in order to improve clamping reliability and accuracy of blocking the cam, the pie and radial teeth of the cam are made with a variable angle of the inclined face moreover, the outer annular sector teeth have a height greater than internal. Sources of information taken into account during the examination 1.Altukhov V.A. Allowance for the commissioning and operation of shelling stankozzz. M., Lesna industry, 1966, p. 32-34. 2. USSR author's certificate number 829421, cl. In 2 D 1/10, 1979 (prototype). s