SU1382596A1 - Plastic housing of reduction gear unit for electric manual all-insulated machine having full isolation - Google Patents

Abstract

The invention relates to electrical engineering, in particular, to a manual mechanized tool with complete isolation. The purpose of the invention is to increase the durability of the hull. The plastic case 1 of the gearbox of an electric hand-held machine with complete isolation is a shell with side walls 8 and an end wall 9 and has a slot 12, which is bore-shaped in sleeve 20, the side surface 21 of which is joined to the side wall 8 by an annular rib 22, located within the seat 23. In the end wall 9 of the housing 1 is complete for one piece with it false-socket. It is located symmetrically to the nest, made in the form of a sleeve 20 relative to the plane of symmetry of the outer contour of the housing, passing through the axis of the nest 12, and has the same dimensions as the said nest. The durability of the machine is achieved by increasing the stiffness of the nests made in the form of tulok, as well as the annular groove 30, designed to install a heat sink in the form of a disk with legs, 8 silt, S (L

Description

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FIELD OF THE INVENTION The invention relates to electrical engineering, in particular, to a fully mechanized handheld power tool. a piece of

The goal of the invention is to increase the durability of the plastic case of the electric manual gearbox with full isolation.

FIG. 1 shows the plastic corius of the reducer of an electric hand-held machine with complete isolation, a slit; in fig. 2 - gearbox housing, section; in fig. 3 view L in FIG. 2; in fig. 4 is a view B in FIG. 2; in fig. 5 shows a section B-B in FIG. BUT; pas figs. 6 - gear housing at the place of installation of the heat sink and assembled with a heat sink, section; in fig. 7 - heat sink, В1щ in plan; in fig. 8 - section GG in FIG. 7

The plastic body 1 of the gearbox of an electric manual machine 2 with full insulation (Fig. 1), in which, for the purpose of double insulation, measles 3 and stator 4 are placed in plastic housing 5 and 6, provides complete insulation of the magine and is a sheath 7 with side walls B and end wall 9. In that part of housing 1 that is adjacent to the manual 11 MaimiHe 2, the shell 7 with side walls 8 is a flag with a deviation from symmetry in

within 5% (100 5%), and the flange 10 has two shells 7, the outer and the inner, interconnected by bridges 11.

ILnacTMaccoBLDi housing 1 contains a slot 12 under the bearing 13 spigot section 14 and a slot 15 under the bearing 16 of the intermediate shaft 17. The socket 12 has a end flange 18 (figure 2). The slot 15 is a sleeve with a end flange 19, which is made in one piece with end wall 9. In case 1, slot 12 is tightly shaped as sleeve 20, the side surface 21 of which is associated with side wall 8 by an annular edge 22 located within bearing seat 23 of the bearing 13. This achieves a uniform shrinkage along the entire perimeter of slot 12 and significant increase stikst. In addition, the location of the annular ribs 22 within the seat e creates

conditions for uniform set-up for bearing 13 and prevents the formation of taper in the socket 5 0

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Yes 12 - a flaw that is characteristic of all nests in which there is no annular edge 22.

The end wall 9 of the housing 1 is integrally formed with a false socket 24. It is made symmetrically to the socket 15 with respect to the plane of symmetry of the outer contour of the housing 1 passing through the axis of the socket 12, and has the same dimensions as the socket 15. Introduction false sockets 24 and the same arrangement ensure uniform shrinkage and constant center of the socket 15 relative to the indicated plane of symmetry.

To increase the rigidity of the housing 1 and the socket 12, the sleeve 20 forming the socket 12 is connected with the side walls 8 of the radial ribs 25, but they are located diametrically, opposite to the centers of the socket 15 and the false socket 24, i.e. on the continuation of the lines connecting the centers I with L and K with L. Such an arrangement of the ribs compensates for the effect of the walls of the sleeve forming the socket 15 and the corresponding influence — the width of the false socket 24.

Movable parts are placed in the plastic case of the reducer, generating heat during operation, which, due to the low thermal conductivity of the plastic, accumulates inside the case 1, which can lead to its deformation. Therefore, an integral part of the housing 1 is a heat sink 26. On the inner side surface of the seat 23 of the socket 12, longitudinal grooves 27 are made, which on one side extend to the front end 28 of the socket 12, and the other end at least in the middle of the seat 23. Side the wall 8 of the housing 1 protrudes axially relative to the end shoulder 18 and on its inner lateral surface 29 an annular groove 30 is formed.

The heat sink 26 is a disk 31 of a material with high thermal conductivity with bent perpieces of the legs 32, its number equal to the number of slots 27. The heat sink 26, whose tabs 32 are located in the slots 27 of the socket 12, is pressed to the front end 28 , 0

As the outer diameter of the disk 31 corresponds to the diameter of the annular groove 30, the annular groove 30 is displaced relative to the front end 28 so that when the periphery of the M disk 31 is inserted into the annular groove 30, the heatsink 26 is pressed against the end 28 of the plastic case 1. For this purpose, the distance x ( FIG. 2) is made smaller than the width o (FIG. 8) of the heat sink 26.

On the surface of the disk 31 of the heat sink 26, a corrugation 33 is made, and in the legs 32 of the blech to the disk 31 - a corrugation 34. These corrugations increase the surface of the heat sink 26, increasing its rigidity and elasticity.

The plastic casing of the gearbox is molded under pressure, with the accuracy of the location of the sockets, dimensional stability and rigidity, it largely depends on the design solution.

Due to the fact that the bearing-bearing seat 12 of the spindle 14 is made in the form of a sleeve 20, the lateral surface 21 of which is joined to the side wall 8 of the housing 1 by an annular edge 22 located in the guides of the bearing seat 23 of the bearing 13, the accuracy of the size of the socket 12 and the nominal location of its axis. The radial ribs 25 also contribute to this due to their diametrically opposite centers (Bearings 15 of bearing 16 of intermediate shaft 17 and false sockets 24, as these ribs 25 compensate for shrinkage caused by merging the sleeve of the socket with the sleeve 20 on the side of the socket 15, as well as on the side false sockets 24.

The annular rib 22 provides a rigid connection of the socket 12 with the housing 1 with uniform shrinkage along the entire perimeter of the sleeve 20, and its location above the bearing seat 23 of the bearing 13, in not at the end face 28, as is usually assumed, eliminates the appearance of the taper of the bearing seat 23 nests 12.

Introducing the false socket 24, symmetrical to the socket 15 relative to the plane of symmetry of the outer contour of the housing 1, passing through the axis of the socket 12 under the bearing 13 of the spindle 14, ensures equal shrinkage conditions of the housing 1.

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Thus, the combination of rigid, 6jni3Koro to full symmetry of the flange 10 of the gearbox housing with the specified design of the sockets 12 and 15 provides high accuracy and rigidity of the entire housing 1. Assembled with the machine (Goy 2, such housing 1 ensures durable operation and complete safety of the operator and In the event that the drill falls into the cables under voltage during operation, the heatsink 26, which pbDi with its legs 32 covers the bearing 13, also serves to extend the durability of the work. in the groove 30 of the housing 1, while the tabs 32 will enter, into the grooves 27 and the heat sink 26 is pressed to the end 28. When assembling, the bearing 13 extends the tabs 32, which cover it with a tension. the bearing 13 is retracted to the heat sink 26 through the tabs 32. Thus, excessive heat is removed from the housing 1, which could lead to deformation of the plastic housing 1.

Due to the fact that the side wall 8 protrudes axially relative to the end collar 18

Yes 12, and the groove 30 for the heat sink 26 is made on the inner side surface 29 thereof, provides additional insulation, since the distance from the outer surface of the side wall 8 accessible to the operator to the heat sink installed in the groove 30 by the periphery of the M disk 31 corresponds to requirements of the GOST. In addition, the groove 30 on the inner surface 29 not only keeps the heat sink 26 in a safe position, but also ensures that it is pressed to the end face 28 of the socket 12, which is necessary to ensure that the tabs 32 contact the subframe 13, the nest

12. The run is provided by the fact that the groove 30 is displaced towards the socket 12 and the distance x between the outer end 28 and the groove is less than the thickness of the disk relative to the heat sink 26.

Due to the combination of the listed structural elements with the heat sink 26, the proposed design of the plastic housing of the reducer of the drill. The machine 2 has a higher rigidity, has a high dimensional stability during casting, in which the deviation of the nests from the nominal location is 8–9 kVA In combination with the heat sink, it provides increased durability of the gearbox housing with complete insulation.

Claims (1)

Invention Formula The plastic housing of the electric manual machine's gearbox is fully insulated, containing a shell with side and end walls, a spindle bearing housing and a bearing shaft for the intermediate shaft in the form of a sleeve with a shoulder, made in one piece with the end wall, characterized in that to increase durability housings, bearing housing of the spindle is made in the form of a sleeve, the side surface of which is adjacent to the side wall of the reducer, and in the end wall is made in one piece with it a false socket, symmetrical to the bearing slot of the intermediate shaft relative to the plane of symmetry of the outer contour of the housing passing through the axis of the socket under the spindle bearing, while the sleeve of the latter is connected to the side walls of the rib, the said side wall projects axially relative to the spindle bearing end shoulder and into its interior An annular groove is formed on the outer surface, which is intended for mounting a heat sink introduced into the housing in the form of a disk in the claws. but / Fig / g FIG. Bb te Fig 5 25 25 77 / /.7 Fig / 30322227 f2 8 21 FIG. about f1 R  rjz Fml 3ff 26 / J2 2 J / 33 Pc / .9