DE2053095A1 - Linear motor in comb or double comb design - Google Patents

Description

Linear motor in comb or double comb design The invention is not applicable on a linear motor in comb or double comb design, with the number of turns each The height of the excitation winding groove is divided into two equally sized sub-coils isolated from one another, for example upper and lower coils, is dismantled in such a way that one each wound together Upper and lower coil in the manner of a two-layer winding in two under certain constant axial distance lying grooves is arranged. The excitation coils generate a traveling field moving in the axial direction as the primary part, which induces a secondary part, one directed in the direction of the traveling field Force is exerted on the secondary part, which is designed as a runner. Has the linear motor only via a laminated core with an excitation winding part (primary part) and a secondary part, so one calls the exciter part because of its comb-like structure as "comb" and entire excitation part as a "single comb", the back shot of the magnetic flux in the The secondary part takes place through the secondary part, which is designed as a laminated core or iron rail.

If two sheet metal stacks opposite one another have a single one in between induce lying secondary part, the excitation part is called a double comb. With this type of linear motor, magnetic flux has two air gaps overcome, but the magnetic Circles through the a-e of the flows both "combs" formed, so that this arrangement for the formation of a large Thrust in the axial direction is favorable. The secondary part is with the double comb Made of an electrically conductive, but magnetically non-conductive material, at least Copper: manufactured.

The excitation coils are available as single or intermediate windings for single or double combing known. Every single turn has the same groove pitch, all individual turns of the same working step form a coil.

The disadvantage of this known arrangement is the fact that a simple solution for changing the traveling field speed is not given. On the other hand, arrangements are known in which a constant change of the winding steps along the traveling field direction a proportional change the traveling field speed is reached. In addition, there is a supply with variable Frequency has been suggested to achieve this goal. However, they were added additional frequency converter required, so that the equipment was great.

The invention is based on the above disadvantages to eliminate creating a simple circuit for a linear motor that does it made possible with two-layer windings and two different traveling field speeds to proceed in the same way as the DAhlander circuit for relatively small numbers of slots, So get by with a single winding for two traveling field speeds.

This is achieved according to the invention in that two associated, jointly wound upper and lower sides of a coil with a groove step in the Order of magnitude of 1/2 to 2/3 of the for the greater traveling field speed corresponding pole pitch wound, all coils of a strand in two each for itself permanently connected halves connected in series and both strand halves firmly are connected, and that the middle of each branch is led out as a tapping point, the beginnings and ends of the three winding phases by 1/3 of the pole pair pitch the higher traveling field speed are offset.

In an advantageous manner, when the strand halves are connected in series the single-delta or single-star connection, in parallel connection of the string halves the double-star connection or double-delta connection is used.

Another feature of the invention is to be seen in the fact that the wanschte Moving field direction either by crossing or not crossing two string connections simultaneously with the traveling field speed and with the same pole-changing switch is adjustable.

Another important feature is that the two one The stator cores forming the double comb are exactly symmetrically opposite to the air gap and for switching the traveling field speed or direction with a common Pole-changing switches are connected.

The windings can also be used to achieve a burning effect Pole pitch can be connected to a direct current network.

The invention is explained in more detail with reference to the drawing: FIG. 1 shows a section of a single comb with the associated secondary part according to the state of the art of the technique, Figure 2 section a double comb with the for both excitation windings common secondary part according to the prior art, FIG 3 shows a comb according to the invention, and FIG. 4 shows an additional exemplary embodiment according to of the invention in a circuit for the supply via the middle of the strand and high traveling field speed.

Figure 5 shows another embodiment of the invention in a Circuit for the supply from the beginning to the end of each strand and lower Traveling field velocity.

In FIG. 1, the primary part 1, 1a, 1b of the stator plate is the field winding grooves 2, 2a, 2b. The actual excitation coils 3 are indicated in several grooves namely as upper and lower coils. The primary part with its excitation winding is separated from the secondary part 6 by an air gap 4. The abutment made of iron is on the upper edge with a metal coating 5, for example made of Ou, Mistake. The s way of transferring the Dahlander circuit from rotary field motor on the linear motor, even with the small number of slots used for small combs. Switching to different traveling field speeds has an advantageous effect with regard to small electrical or magnetic losses as well as during start-up or when braking the linear motor. From the well-known diversity of the Two-layer windings in such motors in a comb design will those with a keying of 1/2 to 2/3 of the pole pitch of the greater traveling field speed proposed in an expedient manner. All coils of a half strand are among themselves firmly connected in series: also the two half-strands. It will also the beginning or the end as well as the middle of each strand of one terminal each guided. From the usual number of terminals in the Dahlander circuit in rotary field motors (6 and 9), the invention selects the smallest (6) because it is the case with rotary field motors the usual terminal strips for linear motors are not readily available as a standard design can be assumed, but because one often has loosely hanging out connecting cables must count, their number to reduce the susceptibility to failure in an advantageous manner is kept as small as possible. , 1'.; The distribution of the three strand connections 1/3 of the pole pair division of the greater traveling field speed at the transition from Rotary field motor on the linear motor is basically possible according to the invention.

The types of supply known from Dahlander circuits in rotary field motors (Single star and single triangle when fed from the beginning and end of the string at half traveling field speed, or. double star and double triangle when powered from the middle of the string to the parallel-connected string ends at full traveling field speed) can be transferred to the linear motor in an advantageous manner according to the invention to switch to different traveling field speeds with a single winding.

In Figures 1 and 2, known designs of linear motors (single and double comb) with associated or common secondary part with two-layer windings shown. The spool width, which is determined by the groove pitch, is subject to change. In figure. 3, however, a stator plate with excitation winding grooves and indicated Two-layer winding shown according to the invention. Here is the range of about 1/2 to 2/3 of the pole pitch belonging to the greater traveling field speed meaningful, including minor tolerances upwards and downwards.

For example, twelve grooves are selected in this embodiment.

The polarization belonging to the greater traveling field speed includes six slot pitches. The selection from the possible grooving steps according to the invention results in 1/2 x 6 = 3 to 2/3 x 6 = 4 slot pitches. Within this range, the Grooving step can be selected in a known manner according to the winding factor. In the exemplary embodiment according to FIG. 4, a winding step of 3 was formed from the difference in the numerical ratio 1: 4 is provided.

In Figure 3 is a circuit diagram with electrical connections for high traveling field speed shown. Opposite to that of the Dahlander circuit in the case of rotary field motors known larger numbers of uses, the invention must be used for short Use combs with a smaller number of slots, as these are otherwise only available for small and micro engines are applicable.

In the exemplary embodiment there are twelve grooves.

In Figure 4, the winding part U1 is X1 as one half of the first Understand strand (phase). The winding part U2 X2 represents the second half of the first strand. Both halves are by connecting X1 and U2 in the The center of the strand is firmly connected to one another. The ends U1, (X1 + U2), X2 are to the Terminals led out.

The second strand is divided accordingly: The winding part V1 Y1 refers to the first half of the strand, V2 Y2 on the second Strand half. Y1 and V2 are firmly connected to one another in the middle of the strand. the Ends V1, (Y1 + V2) and Y2 are brought out. In the third strand you have the strand halves W1 Z1 and W2 Z2. Are connected to each other in the middle of the strand Z1 and W2. The ends W1, (Z1 + W2) and Z2 are in turn led out to Z2.

In order to achieve a high traveling field speed, the In the middle of the line, the connections (X1 + U2), (Y1 + V2) and (Z1 + U2) each from U, V, and W fed.

The beginning and the end of the line are connected in parallel, that is U1 + X2 as X V1 + Y2 as Y W1 + Z2 as ZZ The terminals X, Y and Z are in a double star connection connected.

FIG. 5 shows the circuit diagram for the low traveling field speed. Current flows through each strand in series from the beginning of the strand to the end of the strand.

The beginnings of the strand U1 V1 W1 are connected to the network, as are the ends of the strand X2, Y2, Z2. The middle of the strand is not fed. The ends become U1, V1, W1, X2, Y2 preferably connected in delta.

According to the proposal of the invention, the traveling field moves, for example at the high traveling field speed when feeding from the center of the strand to the Beginning or end of the strand from left to right. In the opposite case, i.e. with The continuous supply from the beginning of the line to the end of the line moves the traveling field at slow speed from right to left.

With optional crossing or non-crossing of two connections of the strings can use a pole-changing switch, which is not shown separately, the desired The traveling field direction can also be changed, as is known with rotating field motors is.

The invention has the particular advantage that it can be switched over to different traveling field velocities with simple switching elements and one single winding is possible. This is for relevant linear motors in comb design important, both with long duty cycles or with many starts. aside from that is the adjustment to the useful ratio in smaller linear motors to the same important to avoid a cumbersome and expensive construction for linear motors Avoid how they are suitable for use in numerous drives.

Claims (4)

Claims 1. Linear motor in comb or double comb design, whereby the number of turns each excitation winding groove in height into two isolated from one another, equal in size Partial coils, for example upper and lower coils, is broken down in such a way that one each Upper and lower coil wound together in the manner of a two-layer winding in two is arranged under certain, constant axial spacing grooves, characterized in that two associated upper and lower sides of one Spool with a groove pitch on the order of 1/2 to 2/3 that of the larger Traveling field velocity belonging to the pole pitch wound, all coils of a strand connected in series in two halves, each firmly connected to each other, as well as both Strand halves are firmly connected, and that the middle of each strand as a tapping point is led out, with the beginnings and ends of the three winding strands around # the Pole pair division of the higher traveling field speed are offset. 2. Linear motor according to claim 1 and 2, characterized in that when the line halves are connected in series, the single-delta or single-star connection, in parallel connection of the string halves, the double-star or double-delta connection is applicable. 3. Linear motor according to claims 1 to 2, characterized in that that the desired wandering field can be achieved either by crossing or not crossing two string connections at the same time with the traveling field speed and with the same Pole switch is also adjustable. 4. Linear motor according to claims 1 to 3 for double combs, thereby characterized in that the two stator laminations forming a double comb exactly symmetrical to the air gap (4) opposite and for switching the traveling field speed or direction are connected to a common pole-changing switch. Linear motor according to Claims 1 to 4, characterized in that the windings are connected to a direct current network with the selected polarity. L e r s e i t e