CN202479842U - Pressing device - Google Patents

Abstract

The utility model relates to a pressing device which comprises a support arm and a pressing arm, wherein the support arm is provided with a support surface. The pressing device is characterized in that the surface of the pressing arm which corresponds to the support surface is provided with a convex pressing ball head. The pressing device is used for pressing by the pressing arm with the ball head, so that point contact is formed between the pressing arm and a workpiece, and a workpiece pressing stress force direction and a workpiece supporting stress force direction are arranged along with one straight line; and therefore, the workpiece can not be bent and deformed caused by bending moment, the effects of positioning and clamping can be effectively realized, and the clamping quality can be improved.

Description

A kind of hold down gag

Technical field

The utility model relates to a kind of hold down gag that is used for the workpiece location.

Background technology

In machining process,, regular meeting carries out following process after utilizing anchor clamps or hold down gag to the semi-finished product location, for example when the clutch housing part of a thin-walled of processing; Carry out following process after just need compressing, because the inwall of part housing own is thinner, therefore in the compaction process of workpiece to the blank location of die casting; Need compress stablely, it is corresponding with the positioning supports face and reliable to compress contact-making surface, stressed preferably point-blank; Otherwise be prone to produce moment of flexure, thereby make part deformation.But in view of this part blank is a die casting, seal face is a black skin, and there is drafting angle in the black skin surface irregularity, and changes bigger.If use the clamping arm of common hold down gag as depicted in figs. 1 and 2, then can cause Work-sheet pressing face contact site uncertain, with the positioning supports face can not be well corresponding.

Stress signal when employing as shown in Figure 3 has the tack clamping arm to Work-sheet pressing now; Workpiece 300 is through the clamping arm 100 on top and support arm 200 clamped the fixing of bottom, and correspondingly support arm 200 provides a positioning supports face, and workpiece 300 suffered clamping arm 100 downward directed force F 1 should be on the straight line with positioning supports towards last directed force F 2; As not on same straight line; Form a moment M, the pressure of oil cylinder is very big in addition, therefore can cause workpiece 300 flexural deformations.And the surface of clamping arm 100 contact parts (being workpiece 300) is a black skin, and surface quality and pattern draft change greatly, and the stress point of F1 changes also greatly, in compaction process, is prone to produce moment M as shown in Figure 3.

Therefore, though common tack clamping arm is simple in structure; But maximum problem is, when compressing on the blank surface, because of the surface quality instability; And pattern draft is arranged; It is uncertain to compress a position, can make Work-sheet pressing, support and to receive force direction not point-blank, be prone to produce moment of flexure and make part deformation.

The utility model content

The utility model technical problem to be solved is to provide a kind of hold down gag, and this device can effectively keep the compacted workpiece uniformity of suffered force direction up and down, and then avoids the improper destruction that workpiece itself is caused that compresses.

Its technical problem to be solved can be implemented through following technical scheme.

A kind of hold down gag comprises support arm and clamping arm, and said support arm has a supporting surface, and its characteristics do, is provided with the bulb that compresses of a protrusion with the corresponding clamping arm of said supporting surface surface.

As the further improvement of present technique scheme, the said bulb that compresses is a steel ball, and said steel ball part is embedded at said clamping arm surface.

As the further improvement of present technique scheme, offer an embedding hole that holds said steel ball on the said clamping arm, the aperture in said embedding hole is less than the sphere diameter of said steel ball.

Be one of preferred embodiment of the utility model, said embedding hole has at the bottom of the awl.

Wherein, the angle of taper at the bottom of the said awl is 120 degree.

Also as the further improvement of present technique scheme, said clamping arm surface is the plane.

Adopt the hold down gag of technique scheme, compress, and the blank surface quality is unstable on the blank surface; Have under the situation of pattern draft, compress, make that forming point between clamping arm and workpiece contacts through using the bulb clamping arm; Make Work-sheet pressing, support receive force direction point-blank; Avoid workpiece to receive moment of flexure and flexural deformation, effectively realized the effect of positioning and clamping, improved the clamping quality.

Description of drawings

Below in conjunction with accompanying drawing the specific embodiment of the utility model being done one specifies.

Fig. 1 is the structural representation of existing tack clamping arm;

Fig. 2 be among Fig. 1 A-A to cutaway view;

Fig. 3 compresses force analysis figure for existing tack clamping arm;

Fig. 4 is the clamping arm structural representation of the utility model hold down gag;

Fig. 5 be among Fig. 4 B-B to cutaway view;

Fig. 6 compresses force analysis figure for the utility model hold down gag;

Fig. 7 is the enlarged diagram at C place among Fig. 6;

---clamping arm 200---support arm 300---workpiece 410---steel ball 420---embedding hole 421---awl end 430---seal face among the figure: 100,400

The specific embodiment

Like Fig. 4 to hold down gag shown in Figure 7; Form by the clamping arm 400 on top and the support arm 200 of bottom; Adopt the bulb clamping arm of some contact, promptly in the embedding hole 420 at the pressure head place of clamping arm 400, embed a standard steel ball 410, and make steel ball 410 outstanding pressure head planes a little.

Wherein, the aperture in embedding hole 420 is more smaller than the sphere diameter of steel ball 410, can guarantee cooperating of steel ball 410 and embedding hole 420 like this, makes being embedded in embedding hole 420 that steel ball 410 can be stable, thereby is convenient to compress.

In addition, for the ease of the processing in embedding hole 420, and help stationary balls; The bottom design in embedding hole 420 is taper, and promptly embedding hole 420 has at the bottom of the awl 421, and the angle of taper at its awl end 421 is 120 degree; The brill angle of this angle and drill bit is complementary, the time processing moulding in the process of being convenient to hole.

Simultaneously; In order to keep the original function of hold down gag; The pressure head plane that is embedded steel ball 410 (i.e. seal face 430 among the figure) still is arranged to the plane, so also can selects for use seal face 430 to combine the supporting surface of support arm 200 to accomplish the task that compresses of workpiece in due course.

Theoretically, since the contact site of spheroid when contacting with the plane for a bit.Therefore use the compacted form of bulb clamping arm, can be so that the steel ball bulb of clamping arm 400 realizes that with the seal face of workpiece 300 point contacts.And through simple designing and calculating; Make the bottom supporting over glaze line of centre of sphere place axis and workpiece 300 of steel ball 410 in alignment; The clamping orientation is accurate, thereby makes workpiece receive force direction F3 and F2 point-blank, has avoided on workpiece forming moment of flexure and the flexural deformation that causes workpiece.

Claims (6)

1. a hold down gag comprises support arm and clamping arm, and said support arm has a supporting surface, it is characterized in that, compresses bulb with the corresponding clamping arm of said supporting surface surface is provided with a protrusion.

2. hold down gag according to claim 1 is characterized in that, the said bulb that compresses is a steel ball, and said steel ball part is embedded at said clamping arm surface.

3. hold down gag according to claim 2 is characterized in that, offers an embedding hole that holds said steel ball on the said clamping arm, and the aperture in said embedding hole is less than the sphere diameter of said steel ball.

4. hold down gag according to claim 3 is characterized in that, said embedding hole has at the bottom of the awl.

5. hold down gag according to claim 4 is characterized in that, the angle of taper at the bottom of the said awl is 120 degree.

6. hold down gag according to claim 1 and 2 is characterized in that, said clamping arm surface is the plane.

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