JPH051776Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a coupling mechanism between an internal frame and a housing in a meter such as a controller.

Prior Art Figures 4 and 5 show a controller implementing the present invention.
Referring to the figure, a recent meter 1 such as a controller has an internal frame 2 and a housing 3.
In many cases, a display board 4 is attached to the front side of the display board, and a printed wiring board 5 is fixed to the back side with set screws 6 (FIG. 1) or the like.

FIGS. 6 and 7 are cross-sectional views showing an example of a conventional coupling mechanism between an internal device frame and a housing, and FIGS. 8 and 9 are bottom views thereof. In the illustrated conventional example, the internal frame 2 has a printed wiring board holding member 7, and the casing 3 has a printed wiring board support groove 8. A tongue piece 9 defined by a gap 10 is provided on the bottom wall of the internal device frame 2 . In FIG. 6, when the tongue piece 9 is pushed up and the inner frame 2 is inserted into the appropriate position of the housing 3, and the tongue piece 9 is released, the protrusion 11 of the tongue piece 9 is inserted into the locking hole of the housing 3. 12 , the inner device frame 2 is coupled to the housing 3 .

To separate the internal frame 2 from the housing 3, push up the knob 9a at the free end of the tongue piece 9 upwards as shown in FIG. , just pull out the internal frame 2.

In the conventional coupling mechanism shown in FIGS. 6 to 9, there is a risk that dust may enter through the locking hole 12 of the housing 3 and the gap 10 of the internal device frame 2. The inner frame 2 can be inserted without opening these locking holes 12 or gaps 10.
If an attempt is made to fasten the instrument with screws, a part of the area of the display panel 4 on the surface of the internal instrument frame 2 will be occupied by the screws, which will be an obstacle to downsizing the instrument. Furthermore, if only the side surfaces of the internal instrument frame 2 are used for connection with the housing, a problem arises in that when the instrument 1 is attached to a control panel, the protruding portion of the instrument 1 from the surface of the control panel becomes too large.

Problems to be solved by this invention Therefore, the problems to be solved by this invention are as follows.
The structure is such that the internal frame can be removably connected to the housing without using holes or screws.

Means for Solving the Problems Referring to FIGS. 1, 2, and 3, in the coupling mechanism according to the present invention, a receiving frame portion 20 is formed integrally with the housing 3, and the receiving frame portion 20 A hook-shaped projection 21 is projected from the inner device frame in the direction of removal, that is, in the direction of arrow C, and a locking gap 22 is defined between the projection 21 and the non-projecting portion of the receiving frame portion 20. 1 to 3 are perspective views seen from the bottom of FIGS. 4 and 5, and only show the main parts of the casing 3. FIG. The arm member 24 is appropriately extended from the side surface of the internal device frame 2, and one end thereof is connected to the locking gap 22.
At the same time, the arm member 24 is made elastically bendable in a direction perpendicular to the direction of attaching and detaching the inner device frame 2, that is, in the direction of arrow A.

A locking piece 23 is formed at the one end of the arm member 24 so that the locking piece 23 can freely engage with the protruding end of the hook-shaped projection 21. Further, an extension portion 25 is appropriately formed on the fixed printed wiring board 5, and the extension portion 25 is attached to the locking piece in the internal device frame 2.
It is placed in the area facing the facing surface of the case No.3.

Operation To connect the internal unit frame 2 to the housing 3, the first
After fitting the internal frame 2 into the receiving frame portion 20 of the housing 3 while pressing down the locking piece 23 shown in the figure with a finger, the finger is released from the locking piece 23. At this time, the locking piece 23 returns upward due to the elasticity of the arm member 24, fits into the locking gap 22, and engages with the protrusion of the projection 21 integral with the housing 3, as shown in FIG. The internal frame 2 is held in a state of being combined with the casing 3 so that the inner frame 2 is connected to the housing 3.

To separate the internal frame 2 from the housing 3, press down the locking piece 23 in the locking gap 22 with your finger, and then move the internal frame 2 to the receiving frame 2 of the housing 3.
Pull it out from 0 in the direction of arrow C. At this time, the locking piece 23
is located below the locking gear 22 and the projection 2 is located below the locking gear 22.
Since it passes under the protrusion of No. 1, the above-mentioned coupled state is released.

Thus, according to the present invention, the locking hole 12 is provided in the housing 3.
The inner frame 2 can be detachably connected to the housing 3 without providing any openings such as the above or using set screws.

When the locking piece 2 is in the connected state shown in FIG.
If an attempt is made to separate the internal frame 2 from the casing 3 without pressing down the internal frame 2 , a bending stress toward the casing 3 acts on the arm member 24 . According to the present invention, this stress is applied to the printed wiring board 5 disposed in the area facing the locking piece 23.
This prevents damage to the arm member 24 due to this error.

Embodiment In the instrument 1 shown in FIG. 5 in which the present invention is implemented, the mounting bracket 30 has a protrusion (not shown) that fits into the hole of the casing 3 shown in FIG. 5, which corresponds to the mounting hole 31 shown in FIG. This is for attaching the instrument 1 to a control panel (not shown) or the like using attachment bolts 32.

Effects of the Invention As explained in detail above, the coupling mechanism of the internal unit frame and the housing according to the present invention includes a projection protruding from the receiving frame integral with the housing in the direction of separation of the internal unit frame, and an inner part that engages with the projection. Since the locking pieces formed on the device frame are further reinforced by the extensions of the printed wiring board, the following effects are achieved.

(a) No hole for a coupling mechanism is required in the casing, and the intrusion of dust can be suppressed.

(b) Since no screws are used, the entire front area can be used effectively for display purposes.

(c) Damage caused by erroneous operation can be prevented since the printed wiring board is reinforced by an extension.

[Brief explanation of the drawing]

1, 2, and 3 are perspective views showing the coupling mechanism according to the present invention, FIGS. 4 and 5 are front and side views of an instrument implementing the present invention, and FIGS. 6 and 7. are sectional views of the conventional coupling mechanism, Figures 8 and 9.
The figure is a bottom view of a conventional coupling mechanism. 1... Instrument, 2... Internal device frame, 3... Housing, 4... Display board, 5... Printed wiring board, 6...
... Set screw, 7 ... Printed wiring board holding member, 8
... Printed wiring board support groove, 9 ... Tongue piece, 10 ...
...Gap, 11... Protrusion, 12... Locking hole, 20...
... Receiving frame part, 21 ... Protrusion, 22 ... Locking gear, 23 ... Locking piece, 24 ... Arm member, 25 ...
Extension part, 30...Mounting bracket, 31...Mounting hole, 3
2...Mounting bolt.

Claims (1)

[Scope of utility model registration request] In a mechanism for removably coupling an internal frame to which a printed wiring board is fixed to a housing, a hook-shaped part protrudes from a receiving frame integrally formed in the housing in the direction in which the internal frame is removed, and is connected to a non-protruding part of the receiving frame. a protrusion defining a locking gap between the ends thereof, one end of which extends from the internal frame so as to be fit into the locking gap, and is elastically bendable in a direction perpendicular to the direction of attachment and detachment of the internal frame; an arm member, a locking piece that can freely engage with the hook-shaped projection formed on the one end of the arm member, and an extension of the fixed printed wiring board formed at a portion of the locking piece that faces the surface facing the housing. A coupling mechanism between an internal frame and a housing.