DE20308048U1 - Key unit for construction has an insertion wheel and a key body which is connected to the insertion end - Google Patents

Abstract

The key unit has an insertion wheel (20) and a key body (10) which is connected to the insertion end. In the middle of the insertion wheel is a many cornered insert (23) which has many block recesses (23) and evenly distributed clamping blocks and supporting blocks. Each clamping block has at least two teeth cutting angles between 57o and 61o.

Description

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Key unit

The invention relates to a key unit, and in particular to a key unit comprising a key body and an insert wheel, wherein the insert wheel can be placed on a screw head or a screw nut for perfect engagement, so that the key unit can be used even if the screw head is worn.

Generally, a conventional wrench has a rod-shaped wrench body. The wrench body has a hexagonal cavity at one end designed to receive a screw head or nut, and its other end, which has a square hole, serves as a lever end.

However, the design of the above-mentioned wrench is not suitable for use with a worn screw head, so the application of the conventional wrench is very limited.

In order to eliminate the above-mentioned disadvantages of the conventional wrench, the invention creates a key unit through a structural change that can also be used when the screw head is worn.

The main object of this invention is to provide a wrench unit whose design is easy to use and which can be used even when the screw head is worn.

This object is achieved by the invention described in claim 1; advantageous developments or further embodiments can be found in the features in the subclaims.

The embodiments of the invention are explained in more detail below with reference to the figures. The figures show in detail:

Figure 1 is an exploded view of a first embodiment of a key unit according to the invention;

Figure 2 shows a cross section of the key unit according to the invention according to Figure

i;

Figure 3 is a side view of the key unit according to the invention as shown in Figure i;

Figure 4 shows a cross section of an insert wheel according to the invention of Figure 1;

Figure 5 shows a cross-section of an insert wheel according to the invention with a worn screw head; and

Figure 6 is an exploded view of a second embodiment of a key unit according to the invention.

First, reference is made to Figures 1 and 2. These drawings show an exploded view and a cross-section of a key unit according to the invention. As can be seen from the figures, the key unit according to the invention comprises a key body 10 and an insert wheel 20.

At one end of the key body 10, a cylindrical insert end 12 is formed for holding the insert wheel 20, the opposite openings of which are provided with a plurality of recesses 13, wherein the recesses 13 are designed as a dovetail guide and each have two lateral inclined surfaces 131.

The insert wheel 20 is cylindrical and has a plurality of protruding lugs 22 on the edge of one end which match the recesses 13 of the key body 10. An insert 23 is defined in the center of the insert wheel 20 and is designed to engage a screw nut or a similar connecting part, the insert being shaped as a polygon. On the inner circumference of the insert 23 there are six evenly distributed block recesses 24, three clamping blocks 25 and three support blocks 26, as can be seen from Figures 2 and 4, the clamping blocks 25 and the support blocks 26 being formed one behind the other. In this preferred embodiment, three teeth 251 are formed on a surface of each clamping block 25, with two teeth 251 intersecting at an angle between 57° and 61°.

Referring to Figures 2 and 3, the insert 23 of the insert wheel 20 is, when actuated, placed on a screw 40. The screw head 41 of the screw 40 has six edges 411 and six side surfaces 412, the edges 411 facing the block recesses 24 and the side surfaces 412 closely abutting against the clamping blocks 25 and against the support blocks 26.

Referring to Figures 2 and 4, when the wrench body 10 is rotated in the opposite direction, the lugs 22 of the insert wheel 20 press against the inclined bevels 131 of the recesses 13, whereby the insert wheel 20 can be firmly connected to the wrench body 10. Because the side surfaces 412 are pressed against the clamping blocks 25 and the support blocks 26 when the wrench body 10 is pivoted, the screw head 41 of the screw 40 engaged in the insert 23 is thereby rotated.

As shown in Figure 5, the insert 23 of the insert wheel 20 is placed on a worn screw head 42, wherein the clamping blocks 25 and the support blocks 26 of the insert wheel 20 can also engage the side surfaces of the screw head 42, whereby the worn screw head 42 of the screw can be rotated by pivoting the wrench body 10.

Referring to Figure 6, a second embodiment according to the invention is shown. In this embodiment, the key unit according to the invention comprises a key body 50 and an insert wheel 60. At one end of the key body 50, an insert end 52 provided with a square nose is defined for holding the insert wheel 60. The cylindrical insert wheel 60 has at one end a square insert hole 61 matching the insert end 52 of the key body 10, the other end being designed as a hollow insert 62 which is designed to engage a screw nut or a similar connecting part. On the inner circumference of the insert 62 there are six evenly distributed block recesses 24, three clamping blocks 25 and three support blocks 26.

According to the above descriptions, the key unit according to the invention can also be used with a worn screw head

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The design of the key unit is easy to handle. This solves the problem of the invention.

Claims (5)

1. Key unit comprising: a key body and an insert wheel 20, characterized in :
that an insert end is formed at one end of the key body for holding the insert wheel 20,
that one end of the insert wheel 20 can be connected to the insert end of the key body 10,
that a polygonal insert 23 is defined in the center of the insert wheel 20, wherein on the inner circumference of the insert 23 there are several evenly distributed block recesses 24, several clamping blocks 25 and several support blocks 26. 2. Key unit according to claim 1, characterized in that at least two teeth 251 are formed on a surface of each clamping block 25, wherein each two teeth 251 intersect at an angle between 57° and 61°. 3. Key unit according to claim 1 or 2, characterized in that the clamping blocks 25 and the support blocks 26 are formed one behind the other. 4. Key unit according to one of the preceding claims, characterized in that the key body 10 has a cylindrical insert end 12, the opposite openings of which are provided with a plurality of recesses 13, the recesses 13 being designed as a dovetail guide and each having two lateral inclined surfaces 131, that the insert wheel 20 has, on the edge of the end connected to the insert end 12 of the key body 10, a plurality of protruding noses 22 matching the recesses 13 of the key body 10. 5. Key unit according to one of the preceding claims, characterized in that the key body 50 has a square nose at its insert end 52 and that the cylindrical insert wheel 60 has a square insert hole 61 at one end matching the insert end 52 of the key body 10, the other end being designed as a hollow insert 62.